HARVARD UNIVERSITY Library of the Museum of Comparative Zoology Bulletin of the Museum of Comparative Zoology AT HARVARD COLLEGE Vol. XC, No. 1 STUDIES OF NEOTROPICAL ANT-PLANTS AND THEIR ANTS By William Morton Wheeler With Fifty-Seven Plates CAMBRIDGE, MASS., U. S. A. PRINTED FOR THE MUSEUM October, 1942 PUBLICATIONS OF THE MUSEUM OF COMPARATIVE ZOOLOGY AT HARVARD COLLEGE The Bulletin and Memoirs are devoted to the publication of investigations by the Staff of the Museum or of reports by spec- ialists upon the Museum collections or explorations. Of the Bulletin, Vols. I to LXXXIX and Vol. XCI, No. 1 and No. 2 have appeared and of the Memoirs, Vol. I to LVI. These publications are issued in numbers at irregular intervals. Each number of the Bulletin and of the Memoirs is sold separately. A price list of the publications of the Museum will be sent upon application to the Director of the Museum of Comparative Zoology, Cambridge, Massachusetts. Bulletin of the Museum of Comparative Zoology AT HARVARD COLLEGE Vol. XC, No. 1 STUDIES OF NEOTROPICAL ANT-PLANTS AND THEIR ANTS By William Morton Wheeler With Fifty-Seven Plates CAMBRIDGE, MASS., U. S. A. PRINTED FOR THE MUSEUM October, 1942 No. 1. — Studies of Neotropical Ant-Plants and Their Ants 1 CONTEXTS PAGE Part I. The Neotropical Ant Plants. Chapter 1 . The Myrmecophytes of the Genus Cordia ... 3 A. The Cordias of the Section Physoclada .... 4 B. The Cordias of the Section Gerascanthus .... 9 Chapter 2. Observations on Triplaris 41 A. Historical 41 B. Triplaris surinamensis Cham, and Schl 50 C. Triplaris americana Linrie 54 D. Triplaris auriculata Meisner 63 Chapter 3. Observations on Tachigalia 65 Chapter 4. Observations on Cecropia 69 Chapter 5. Observations on Rubiaceae and Yerbenaceae . . 88 A. Duroia and Remijia 88 B. Patima formicaria Johnston 91 C. Clerodendron Siphonanthus R.Br 93 Chapter 6. The Myrmecophytic Acacias 94 A. The Bull-horn Acacias 94 B. Acacia cavenia Hooker and Arnott 116 C. The African Acacias 118 Chapter 7. Various Non-myrmecophytic Plants with Ant-inhabited Stems, etc 119 Chapter 8. The Epiphytic Bromeliaceae and their Fauna . . 133 References 144 Part II. Neotropical Plant Ants 155 Part I. THE NEOTROPICAL ANT PLANTS Chapter 1 THE MYRMECOPHYTES OF THE GENUS CORDIA The more than two hundred known species of Boraginaceous trees and shrubs of the genus Cordia, distributed over the tropics of both hemispheres, have been divided by botanists into several groups, or sections. Two of these, the Physoclada (Pilicordia) and Gerascanthi, are confined to the Neotropical Region and contain several ant-plants, or myrmecophytes, of unusual interest. The most typical representa- tive of the Physoclada is Cordia nodosa Lamarck of Northern South ■Revised for publication by Dr. Joseph Bequaert. Published with the aid of a special gift from Mr. George R. Agassiz. 4 bulletin: museum of comparative zoology America, and perhaps the only true myrmecophyte in the Gerascan- thus section is C. alliodora Ruiz and Pavon, which ranges from North- ern Mexico to Bolivia and eastward over the Antilles and portions of Northern South America. The following account is concerned pri- marily with these two species which I have had abundant opportunity to observe in the field, the former in British Guiana, the latter in Panama. (A) The Cordias of the Section Physoclada Professor I. W. Bailey and I found C. nodosa to be common, both in the primeval forest and in the second-growth jungle about Kartabo, Kalacoon, Barakara and on Great Batavia Island in the Cuyuni River, British Guiana. This and closely allied species have been frequently described by botanists, notably by Beccari (1884-'86), Schumann (1888), Schimper (1888), Mez (1890) and Ule (1907). Though C. nodosa may attain a height of 10 or 12 feet, most of the specimens are small, symmetrical bushes, with verticillate branches, and growing in the shade of tall trees and on low but not inundated soil. The whole plant, including the stem and the large ovate leaves, is covered with long reddish hairs. As Bailey (1924) says, the leaves "are alternate, paired or grouped in false verticels of four. The subnodal portion of the stem, subtending each verticel of leaves, is strongly thickened and angular and usually, though not invariably, provided with a long bladder-like swelling. This pouch is jacketed internally as well as externally, by a cuticularized epidermis and numerous trichomes. It subtends the lowermost of the four leaves, in the axil of which is a small apical outlet which is not excavated by the ants. Above this leaf, the thickened and much compressed primary axis gives rise to lateral inflorescences which are inserted in the axils of the three re- maining leaves." There has been much difference of opinion concerning the morph- ology of these ant-inhabited cauline swellings, which always occur immediately below each node with its verticel of leaves or branches. Schimper believed that the swellings are really the lateral enlargement of the base of the petiole of the lowermost leaf, which is adnate to the main axis. Schumann regarded the inflorescence as terminal and the swellings as cauline rather than as adnate foliar structures. Mez maintained the same opinion in regard to the inflorescence, but inter- preted the swellings as formed by lateral invaginations, which he be- lieved to have been originated by small insects living in the lateral wheeler: neotropical ant-plants and their ants o grooves and later to have been inherited as ant-domatia. Bailey (1924) after a careful study of these structures reaches the following con- clusion: "What then is the morphological significance of these extraordinary structures? The hypotheses of Schimper, Schumann and Mez do not afford an adequate explanation of all phases of their ontogenetic and phylogenetic development. Below the subnodal hypertrophy, the stem is of normal structure. Above this level, it rapidly increases in girth. As it does so, the circumference of its concentric layers of epidermal, cortical and fibrovascular tissues becomes correspondingly enlarged, and a commodious internal cavity is concomitantly formed in the dilated core of medullary parenchyma. This chamber, unlike that of the caulinary domatium of other myrmecophytes, is charac- terized by being jacketed by centripetal layers of epidermal, cortical and more or less rudimentary fibrovascular tissues. There is, in other words, no indication of a compressed stem and adnate petiolar en- largement, nor of an extensive lateral invagination. The centripetal layers of epidermal, cortical and fibrovascular tissues unite with the homologous centrifugal layers only in the apical portion of the wall of the domatium which surrounds the small circular aperture. "A detailed study of the morphology of the myrmecodomatia, during successive stages of their ontogeny, indicates very clearly that they are hypertrophied portions of the cauline axes, whose medullary cavities are jacketed by layers of invaginating tissues. The invagina- tion does not originate, however, in a longitudinal lateral groove, but in the axil of one of the leaves of the pseudo-apical verticel. As it develops, it produces an elongate-saccate ingrowth of the epidermal, cortical and fibrovascular tissues into the rapidly enlarging core of medullary parenchyma. The absence of even a rudimentary bud in the axil of a leaf which subtends an entrance aperture suggests that this growing point may be concerned in the formation of the invagina- tion. If it is, the invagination may be visualized as the homologue of an ingrowing lateral shoot, and its formation may be likened to what happens when one finger of a glove is retracted so that it ultimately projects inwards instead of outwards. In exceptional cases, invagina- tions may develop in the axils of two of the leaves of a single verticel." Prof. Bailey figures an abnormal compound domatium of this type. (1924, pi. 7, fig. 8)._ It is clear from this account and indeed from the most cursory study in the field that the myrmecodomatia of C. nodosa are preformed structures, which cannot be regarded as galls, or as hypertrophies 6 bulletin: museum of comparative zoology produced by insects or fungi. The same statement is undoubtedly true of the corresponding structures in C. hispidissima D C. 1 In this species, however, which seems to be common in Amazonas and Bolivia, but was not encountered in the hyleea of British Guiana, the cauline swelling is asymmetrical, that is, one-sided. Bailey, who has studied its structure on materials collected by Dr. Orlando White and Dr. W. M. Mann on the Rio Beni, in Bolivia, finds it to be funda- mentally the same as that of C. nodosa, though differing in morpho- logical details. "The striking difference in their external form is due to the fact that in the case of the former plants (hispidissima), the subnodal enlargement of the stem is unilateral and the basal projection of the trace of the leaf which subtends the entrance aperture is set off from the central cylinder at a much lower level." C. hispidissima has been recently observed by Bequaert (Wheeler & Bequaert, 1929, p. 28) on the Lower Rio Branco, Brazil. In his ac- count of the domatia he agrees with Bailey and states that they con- tained a "varied fauna". "One swelling contained a book-scorpion (Chelifer) occupying the lowermost portion of the cavity which was enclosed above by a white web-like partition ; another was occupied by a medium-sized spider. Other domatia contained small colonies of a Ponerine ant, Neoponera unidentata Mayr var. eburneipes Wheeler. Each of these colonies consisted of four to six workers, with eggs, larvae and pupae, the last enclosed in cocoons." Chodat and Carisso (1920) describe and figure another Cordia (C. chacoensis Chod.) from Paraguay, which has true domatia somewhat resembling those of C. nodosa and hispidissima, though longer and more slender. This Cordia grows in moist places and is of small size like the species of the Section Physoclada. Unfortunately no account is given of the structure of the domatia or of their tenants. Up to the present time the following ants have been taken in the cauline swellings of C. nodosa and hispidissima in various parts of South America: (1) Neoponera unidentata Mayr var. eburneipes Wheeler. In C. nodosa and hispidissima. Brazil (Bequaert); British Guiana (Wheeler). (2) Pheidole (Hendccapheidole) taehigalioe Wheeler. In C. nodosa, British Guiana (Wheeler). ■Engler and Prantl, IV, 3, 1897, p. S3 recognize only one species, C. nodosa, in the section Physoclada and regard hispidissima D C. and miranda D C. as "wohl von der vorstehenden Art nicht specifisch verschieden." avheeler: neotropical ant-plants and their ants / (3) Crematogaster (Orthocrema) brasiliensis Mayr var. ludis Forel. In C. nodosa. British Guiana (Wheeler). (4) Allomerus 10-articidatus Mayr subsp. 8-articulatus Mayr. In C. hispidissima. Bolivia (W. M. Mann). (5) Allomerus 10-articulatus subsp. 8-articulatus var. exsanguis Wheeler. In C. hispidissima. Bolivia (W. M. Mann). (6) Allomerus 10-articulatus subsp. 8-articulatus var. demerarce Wheeler. In C. nodosa. British Guiana (Wheeler). (7) Allomerus 10-articulatus subsp. 8-articulatus var. angulatus Wheeler. In C. hispidissima. Bolivia (W. M. Mann). (8) Solenopsis tenuis Mayr. In C. hispidissima. Bolivia (W. M. Mann). (9) Azteca brevicornis Mayr var. boliviana Wheeler. In C. hispidis- sima. Bolivia (W. M. Mann). (10) Azteca delpini Emery. In C. nodosa. British Guiana (Wheeler). (11) Azteca duckei Forel. In C. nodosa. Brazil (Ducke). (12) Azteca Stanley uli Forel. In C. nodosa. Brazil (J. Huber; Chodat). (13) Azteca olitrix Forel. In C. nodosa. Brazil (J. Huber). (14) Azteca idei Forel var. cordix Forel. In C. nodosa. Brazil (Ule); British Guiana (Wheeler). (15) Azteca ulei var. gagatina Wheeler. In C. hispidissima. Bolivia (W. M. Mann). (16) Azteca ulei var. gibbifera Wheeler. In C. hispidissima. Bolivia (W. M. Mann). (17) Azteca ulei subsp. nigricornis Forel. In C. nodosa. Brazil (Ule). (18) Azteca trigona Emery subsp. mediops Forel. In C. nodosa. British Guiana (Wheeler). (19) Azteca velox Forel subsp. nigriventris Forel. In C. nodosa. British Guiana (Wheeler). (20) Brachymyrmex heeri Forel. In C. nodosa. British Guiana (Wheeler). (21) Myrmelachista schumanni Emery var. cordincola Wheeler. In C. hispidissima. Bolivia (W. M. Mann). Most of these forms and notably the species of Neoponera, Pheidole, Crematogaster, Solenopsis, Brachymyrmex and Myrmelachista are of infrequent occurrence and found only in single domatia. The same seems to be true of the species of Azteca, but the forms of Allomerus 8-articulatus are regular, or obligate tenants. This is certainly the case in C. nodosa in British Guiana, where the var. demerarx was found 8 bulletin: museum of comparative zoology in every one of the plants examined and usually inhabiting all of its eauline swellings. As the habits of this ant are practically unknown, I single it out for special consideration. The genus Allomerus was established by Mayr in 1877 for some small yellow worker ants taken by Prof. James Trail in Northern Brazil, presumably in the eauline swellings of Cordia or of some other myrmecophyte. In 1904 Forel described all three phases of 8-articulatus taken in Amazonas by E. Ule in the petiolar sacs of Tococa setifer Pilger and observed that the females and males were of a much darker color and larger size (6 and 5.3 mm. respectively) as compared with the workers (1.8 mm.). Misled by a false analogy with the ants of the genera Solenopsis, Carebara, etc., he surmised that the Allomeri might be thief-ants. This is clearly disproved by my observations. The genus, as Emery has shown (Genera Insect., Myrmicinse, 1921, p. 188), belongs to the tribe Monomoriini and not to the Solenopsi- diini, which comprise so many lestobiotic species. Allomerus 8-articulatus var. demerarae is well known to the native Indians of British Guiana, who call it the "Kurabelli" (Hohenkerk, 1918). Its colonies are extremely populous, comprising thousands of workers and many mother queens. Each colony normally occupies all or most of the eauline swellings of a C. nodosa bush or tree. All the cavities are connected with one another and with the forest floor by a peculiar system of galleries or arcades, constructed on the surface of the plant by the ants and measuring about 5-10 mm. in diameter. They consist of minute particles of black, agglutinated earth built up around and supported by the long red hairs above mentioned. A single gallery starts at the ground and ascends the trunk in a straight line to the first node, where it ramifies and sends a branch along the surface of each limb of the verticel. The branching is repeated at succeeding nodes till each swelling is furnished with a gallery that runs up its side and terminates at the orifice of the cavity. The minute, pale, yellow, small-eyed workers are thus enabled to pass under a continuous carton-like roof and between the stiff hairs which support it like so many pillars, from their nests in the domatia to the ground where they forage among the dead leaves. Coccids (Pseudococcus brevipes) are found in some of the domatia but they are not sufficiently numerous to provide more than an insignificant portion of the food required by so large an ant-population. This consideration and the elaborate construction of the system of galleries show that while the ( ordia furnishes most admirable domatia for the ants, it is by no means an adequate source of food. wheeler: neotropical ant-plants and their ants 9 During the rainy season (July to September 1920) I found the cauline swellings full of the Kurabelli brood in all stages, together with many males and winged females. As soon as the swellings on the youngest branches become large enough, dealated females take possession of them and begin, apparently at once, to lay eggs. And though each incipient swelling usually contains only a single young dealated female, I have on several occasions found two, three or even four such females, all caring for their eggs or young larvae in common in the same domatium. Unlike most ants, therefore, Allomerus is normally pleometrotic even during the incipient stages of colony formation. After they are reared the broods of these young females undoubtedly become a part of the single large polycladic colony which possesses the whole plant. It cannot be maintained that the Kurabelli act as an efficient pro- tective body guard for the Cordia, at least so far as man .and the larger animals are concerned.. When one handles the plant for some time, the workers do indeed swarm over one's clothes and body and for some time keep on stinging, but their stings are so feeble that they produce merely a rather unpleasant itching and that only of parts with very thin epidermis. While it is probable that the Kurabelli may be more efficient in keeping the plant free from certain insects, it should be noted that other Formicidae not infrequently occupy some of the domatia although most of them may be tenanted by Allomerus; and both Professor Bailev and I sometimes found the foliage of such plants considerably damaged by leaf-cutting ants (Atta cephalotcs). I have also noticed leaves that had been extensively gnawed by caterpillars. The foliage of one plant tenanted by Allom- erus was covered with Cecidomyid galls. The only other insects found associated with C. nodosa were termites, which on one occasion were seen to have a gallery extending up the trunk from the ground and terminating in a cauline swelling which they were occupying. (B) The Cordias of the Section Gerascanthus The Cordias of this group, unlike the Physoclada, are tall shrubs or trees, frequently attaining a height of 20 to 60 feet, with gray bark and coriaceous, opaque leaves, covered with dense stellate hairs be- neath and sparser hairs of the same type above. The branching, except in young specimens, is much more obscurely verticillate, and though ant-inhabited cauline swellings occur in some of the forms, they are much simpler than those of the Physoclada, being merely 10 bulletin: museum of comparative zoology conical, pyriform or turbinate dilatations of the stem beneath and at the nodes, with large medullary cavity and without a preformed orifice. The flowers are much more numerous and showy and usually aggregated in broad, dense panicles or corymbs. As a rule, the plants grow on higher ground, in the campos or more open woods and thickets and therefore in more xerothermal stituations than the Physoclada. Chodat and Vischer (1920) recognize seventeen species as belonging to the Gerascanthus section, but many of the forms are by no means easy to distinguish, as may be inferred from their remarks: "After a thorough examination of the flowers of all the species, we have been unable to discover other characters than those derived from the size of the organs, the more or less elongate form of the ovary or of the infraovarian disc, the importance of which is in no respect greater than that resulting from an examination of the vegetative organs and the external appearance of the calyces and corollas. The evaluation of the characters derived from a comparison of the reproductive struc- tures is rendered difficult by the fact that there is in the Cordias, at least of this group, a pronounced heterostyly We are, in fact, dealing with species which are but feebly defined morphologically and the taxonomy of which will require revision from time to time as observations in the field increase in number". The authors call attention to the fact that Schumann (1888) regarded all the forms of the Gerascanthus section as constituting but a single species. Of the seventeen species recognized by Chodat and Vischer, nine are recorded as certainly possessing cauline swellings and as being therefore myrmecophilous, namely C. gerascanthus L. and its varieties, alliodora Ruiz and Pavon, Rusbyi Chodat, Hassleriana Chodat, glabrata var. orbicularis Chod. and Vischer, longituba Chod. and Vischer, Chamissoniana Steud., Cuyabensis Manso and Lhotsk. and gerascanthoides HBK. They failed to detect myrmecophily in C. hy-poleuca D C. and excelsa D C. and in certain large-flowered species not belonging to the Gerascanthus section, namely insignis Cham., nettoana Taubert, Hainkeana Mez and formosa Chod. I may add, in this connection, that I have failed to find any indications of myrme- cophily in C. lutea, which is very common in the Galapagos Islands. It has no cauline swelling and ants merely visit its clusters of showy yellow flowers for their nectar. The same is true of the beautiful, vermilion-flowered C. sebestena L., which is common in gardens and along road-sides in the West Indies. wheeler: neotropical ant-plants and their ants 11 Among the myrmecophilous species cited by Chodat, C. gerascan- thus is given as the most widely distributed and best known. He dis- tinguishes three forms or varieties of the plant: genuina Chod. (= gerascanthoides Rich, non H B K), Martinicensis Chod. and micrantka Jacq. The first is cited as common in the Antilles (Cuba, Porto Rico, Jamaica, Haiti, St. Thomas, St. John, Antigua, St. Vin- cent, Trinidad), the second as known from Martinique and Guada- loupe, the last from Mexico, Guatemala, Nicaragua, Costa Rica, Panama, Peru and Bolivia. This form has somewhat smaller flowers than the West Indian type (C. gerascanthus L. sens. str. or genuina) and has been cited by authors as C. gerascanthus Jacquinius. This interpretation of gerascanthus is not accepted by Dr. I. M. Johnston (1924), of the Gray Herbarium, to whom I submitted speci- mens of the species I studied in Panama for identification. I quote his remarks on the synonymy of gerascanthus and alliodora: "In 1910 Urban, Symb. Antil. IV. 516 indicated, that, as then used, the bi- nomial Cordia gerascanthus L., was incorrectly applied to the widely distributed tree with canescent, densely stellate calyces, and that the name is properly applicable to the relatively localized species of the West Indies and Southern Mexico which has glabrous or sparsely hirsute calyces and larger flowers, and which was described and current as C. gerascanthoides HBK. Ten years later, in his paper on Cordia Gerascanthus Chodat, I.e. declared Urban's interpretation of C. gerascanthus L. to be incorrect, and used the term in the tradi- tional sense, applying it to the widely distributed plant with stellate calyces. Further examination of this matter has recently been made to determine the correct specific name for use by Dr. W. M. Wheeler in his publications on myrmecophytes. For the convenience of others the results of this study are here put on record. Cordia gerascanthus L. is based upon the Jamaican plant which Patrick Browne, 1. c, described and figured under the name "Gerascanthus". Browne's illustration, showing only the floral structures, portrays a corolla of large size which has broad short obtuse lobes with conspicuous pinnate veining, a broad saucer-shaped throat, a stocky weakly ribbed calyx, and deltoid calyx lobes. These characters definitely associate Browne's plant with C. gerascanthiodes HBK. and prohibit the use of the Linnean name for the plant with stellate calyces. It is to be also noted that not only does Grisebach, 1. c. cite Browne's figure under "C. gerascanthoides H B K.," but he gives C. gerascanthoides HBKas "common in the lowlands and mountains" of Jamaica, and gives the plant with stellate calyces (under C. gerascanthus Jacq.) as "rare" on 12 bulletin: museum of comparative zoology that island. Browne's plant was not rare, for he speaks of it as follows. "This tree grows in many parts of Jamaica, and is generally esteemed as one of the best timber woods of the island; it rises to considerable height . . . , especially in the lowlands, where it is most common, . . . "It is significant that concerning the Jamaica occurrence of the plant with stellate calyces, Urban, I.e. (under C. alliodora Cham.), comments parenthetically as follows, "fortasse a cl. Wilson introducta ex cl. Stapf. in lit." Since the identity of C. gerascanthoides H B K. and Gerascanthus Browne is certain from a study of Browne's plate and description, and from distributional considerations, it is evident that Cordia gerascanthus L. is, indeed, improperly applied to the widely distributed plant with stellate calyces. Among its close rela- tives in the West Indies and Central America, C. gerascanthus L. is readily recognized by its large flowers, saucer-shaped throat, hirsute or glabrescent stout weakly ribbed calyx-tube, and deltoid calyx lobes. It is known only from Cuba!, Isle of Pines!, Jamaica!, southern Mexico!, and northern Central America. As Urban, Symb. Ant. IV. 516 (1910) and VIII 574 (1921), has pointed out, Cordia alliodora (R. & P.) Cham, is the correct name for the widely distributed plant with stellate calyces, or in other words, for the one incorrectly current as "C. gerascanthus". Cordia alliodora ranges from Mexico and the West Indies southward along the Andes to Bolivia. A number of critical species, doubtfully distinct from it, have been described from Brazil, adjacent Paraguay and Argentina". It is clear, therefore, that at least two quite different species of Cordia have been confused in the literature, C. gerascanthus Linn. ( = gerascanthus Browne = gerascanthoides H B K = gerascanthoides Griseb.) of the West Indies and C. alliodora R. and P. ( = gerascanthus var. micrantha Chodat), distributed from Mexico to Bolivia and also occurring, though apparently not very abundantly, in the W T est Indies. Now C. alliodora always has preformed domatia whereas these structures do not occur in gerascanthus L. Chodat, who has interpreted all the cauline thickenings in the group of Cordias under consideration as insect galls, has simply obscured and confused the whole subject, because while both species may have occasional stem- galls produced by insects, these galls have nothing to do with the pre- formed myrmeeodomatia which are a conspicuous and constant feature in C. alliodora. This matter will be discussed in greater detail in the sequel. I may add that a very competent dendrologist, Professor J. G. Jack of the Arnold Arboretum, has at my request carefully studied many specimens of gerascanthus L. at the Harvard Botanical Garden wheeler: neotropical ant-plants and their ants 13 at Soledad, Cuba and reports that he has utterly failed to find the slightest traces of myrmecodomatia in this species. I admit the possibility, however, that the Panamanian C. alliodora may differ varietally from the Peruvian type described by Ruiz and Pavon, for the following reasons: (1.) The original figure represents the flowers accurately but does not show the cauline swelling which should be present at the base of the panicle. Of course, either the draftsman or the authors may have omitted it owing to its resemblance to a gall. (2.) The authors state that the tree blooms in July and August, whereas the Panamanian tree is leafless at that season and blooms in spring. (3.) According to Ruiz and Pavon, the Peruvian Indians use the bark and leaves as a condiment. The bark and foliage of the Panamanian tree seem to have no such properties. (4.) The following peculiarities cited by Ruiz and Pavon, do not apply to the plants I have examined: "Cum hujusmodi arbores secantur, odorem gravissi- mum emittunt, et penetrantissimum, qui oculorum aciem perstringit. Corticis recenter evulsi odorem valde fcetidum vulpis urinae haud multum adsimilem, spirant; postea vero Foli uti etiam Cortex, allium maxime redolent, unde nomen ab Incolis Arbor accepit." After calling Dr. Johnston's attention to these considerations, he agrees with me that the plant usually cited as C. Gerascanthus Jacquinius and more recently as var. micrantha Chodat of that species, may differ from the typical alliodora. I quote from one of his letters received February 23, 1924: "In regard to Cordia, I must say that I am unable to give you any thoroughly satisfactory information. The plant which Chodat treats as Cordia gerascanthus var. micrantha is newly published by him, although from Chodat's citations one might obtain the impression that the trinomial was based upon a name published by Jacquin. Chodat apparently wished to show that his form micrantha was based upon and included the plant described and figured in his Stirpium americanarum 43. t. 175, fig. 16 (1763). Unfortunately, however, Jacquin's figure shows a flower 17 mm. long, whereas Chodat describes his forma micrantha as having corollas 1 cm. long. In other words, Jacquin's plant is the common form growing in the West Indies, and the plant which Chodat describes is the common form of Mexico and Central America. Wright's plant from Cuba is probably the same form as that figured by Jacquin. I have talked the situation over with the men at the Gray Herbarium and the general consensus of opinion appears to be that Chodat's forma micrantha had best be taken as covering the plant described, rather than as being typified by the cited specimen or the reference to Jacquin. With this solution of the 14 bulletin: museum of comparative zoology problem I am now inclined to agree. If it is satisfactory to you Chodat's trinomial will be applicable to your Panamanian form. The situation will undoubtedly lead to confusion since certain workers are inclined to lay more weight on the specimens cited than upon the actual description, and such people would treat Chodat's trinomial as applying to the large-flowered West Indian form of alliodora. This and other aspects of Chodat's work on Cordia has led me to believe that it has given more confusion than it can possibly give help. Certainly it has not clarified the classification of that large and difficult genus. Intercategorical priority not being recognized in botany, I can and will describe the Mexican and Central American plant as a geo- graphical variety of alliodora, giving it a new name and one definitely applicable to your plant." Since this name is not yet published, I am using the specific name alliodora for the small flowered plant, with preformed myrmecodomatia and a distribution from Mexico to Bolivia. 1 The confusion between gerascanthus Linnaeus and alliodora Ruiz and Pa von has, of course, led to confusion in the writings of those who have considered their relations to the ants. I therefore take up in chronological sequence the various authors who have been concerned with the Panamanian species. One of the earliest, if not the earliest accounts of the relations of ants to Cordia, is that of Ruiz and Pavon (1799), who described and figured C. alliodora (called the "arbol del ajo" an account of its onion-like odor) from Peru under the name Cerdana alliodora. They observed that "qusedam exiguse Formicae quarum punctlo acrem intolerabilemque pruriginem diu persistentem excitat, frequenter has arbores infestantes folia devorant, ita ut vix ulla inveniri possint integra." The first part of this sentence seems to refer to some species of Pseudomyrma, but the latter part is erroneous, since no ants devour foliage, and if it refers to the leaf-cutting Attini, they neither sting nor occupy the cauline swellings of Cordia. Chodat seems to have been led by the remark of Ruiz and Pavon to a peculiar and partly erroneous interpretation of the peculiar carton dissepiments (vide infra) in the cauline swellings and of the habits of their ant-inhabitants. Spruce (1869 [1908]) was also familiar with C. alliodora, which he cites under the name gerascanthus Jacq. He says that "it rises to a stoutish tree 30 to 40 feet, and is throughout fasciculately branched ■Since this passage was written I find that Standley, in his works both on the Mexican (1924) and Panamanian flora (1928), has accepted C. alliodora as the correct name of the plant which I studied. wheeler: neotropical ant-plants and their ants 15 (branches 3-5-nate). At the point where the branches divide there is mostly a sac, inhabited by very vicious ants of the tribe called 'Tachi' by the Brazilians." These ants are undoubtedly a species of Pseudo- myrma and, in all probability, some form of Ps. sericea Mayr or Ps. gracilis Fabr. Seemann (1852-1857), in his early account of the Panamanian flora shows that he was acquainted with C. alliodora (cited as gerascanthus Jacq.), which, he says, is called "laurel" by the natives, who use its wood in building and cabinet making. Although he records the tree as common on the outskirts of woods in the provinces of Panama and Veragua and as growing as far north as Mazatlan and Acapulco, Mexico, he says nothing about the peculiar cauline swellings and their tenants. The same remark applies to Saldanha da Gama (1S74), who cites C. alliodora as distributed throughout Brazil and as known under the name "lauro". It is described as a large tree of such rapid growth that it may yield planks in only eight years after germination. The wood is described as odorous, light and nonresistant to moisture and as being used for doors in the interior of houses, lintels, etc. The carpenters who saw it become very thirsty, owing to peculiar properties of the sawdust, and the shavings withdraw so much moisture from the hands that the workmen find it an unpleasant wood to handle. There is nothing in Saldanha da Gama's description to prove that his C. alliodora is identical with the Panamanian species. Beccari (1884) was the first to give a clear description and figure of the cauline swellings of C. alliodora (cited as gerascanthus) from Mexico. He mentions the plant as occurring in the Sierra Padro Nolasco, at Talca, Acapulco, etc. The peculiar convoluted or travecular carton in the cavity of each swelling was figured and described, and he noticed the entrance holes made by the ants and the large coccids kept by them on the walls of the cavity. He was also quite clear in regard to the structural differences between the swellings of alliodora and those of the Physoclada (C. nodosa). Schumann (18S8), after a brief revision of the Cordias of the geras- canthus group, confirmed but added nothing to Beccari's statements concerning the Mexican alliodora. More than twenty years ago Mr. C. H. Tyler Townsend sent me a number of cauline swellings of alliodora which he found near Cualata, on the slopes of the Volcan de Colima, Mexico. Referring to his letter of August 6, 1902, I find the following note: "The ant from Cualata which keeps a large red lecanoid coccid in its nests in swollen joints of the branches of a tree is probably a new species. This is a most striking 16 bulletin: museum of comparative zoology instance of the interrelations and mutual dependence of plant, ant and coccid." Professor Forel, to whom I later sent specimens of the ant, de- scribed it as Azteca longiceps Emery subsp. patruelis (see Pt. II p. 233). The specimens of the cauline swellings and Coccids, still in my collec- tion, are precisely the same as those described below from Panama. They bear the following note in Townsend's handwriting: "July 25, 1901. Living in hollow cavities in swollen joints of tree growing 12 to 20 ft. high. Cavities in these joints are natural. Ants keep coccids in- side. Small hole or holes allow exit of workers only. These holes are sometimes found grown over, the ants having failed to keep them open, in which case the dead ants are found inside. Joints are inhabited all the way from twigs to branches an inch in diameter. The ants bite." Pittier (1908) in his work on the economic plants of Costa Rica, cites alliodora under the name gerascanihus Jacq., with the following note: "The laurel is one of the most important trees of the country as wood for construction. The trunk is straight, with white bark; the leaves are small, entire, elliptical-lanceolate; the flowers white, very fragrant and in large racemes. The wood is rather fine and hard, of a pale chestnut color and easy to work; it is reputed to be incorruptible and is used principally for flooring. The laurel grows on both slopes of the country from sea-level to 1500 m. more or less, but attains greater di- mensions on the Atlantic Slope." Pittier gives the Bribri Indian name of the tree as "dze-ui." l Ule (1907) observed C. gerascanihus Jacq. (evidently alliodora) at Tarapoto, Peru, in a rather dry region and, after describing the cauline swellings, remarks that "they make the impression of galls, but are thin-walled and nearly always harbor in their cavities a very vicious species of ant, Pseudomyrma sericea var. cordiae Forel." Dr. W. M. Mann, while on the Mulford Expedition to Bolivia dur- ing 1921-22, made observations on C. alliodora (probably var. boliv- iana Chod. & Visch.) and collected ants and other insects in the domatia. These structures are precisely like those of the Central American and Mexican trees. Bailey (1924), who made a study of the structure of the cauline swellings of C. alliodora (cited as gerascanthus Jacq.) from herbarium specimens, remarks that "the domatia vary greatly in size, shape and 'According to Boulger (190S) the wood of C. gerascanthus L. of the West Indies is known in commerce as "bois de Cypre", "prince-wood", "Spanish elm", "Dominica rose-wood" and "bois de Rhodes" and is "dark brown with dusky, excentric zones, open-grained, soft, durable." He says that it is used in cabinet-work. According to Maza and Roig. (1906) C. gerascanthus and g'erascanthoides are called by the Cubans "capa rota", "palo de rosa", "palo de rosa del pais." The wood of gerascanthoides is said to be one of the most valued in Cuba, of a dark chestnut color and to be employed in rural carpentry. wheeler: neotropical ant-plants and their ants 17 distribution in different representatives of even a single species. When present, they are irregularly shaped hypertrophies of the axis of the large diffuse inflorescences or of the transitional region between cauline and floral axes. The lateral entrances or exits are not preformed apertures, as in the Physoeladse, but evidently are excavated by in- sects. Furthermore, the domatia are not jacketed internally by in- vaginated layers of epidermal, cortical, and fibrovascular tissues. As shown in fig. 3, a transverse section of a myrmecodomatium of Cordia Gerascanthus Jacq. (Herbarium J. D. Smith no. 4365), the inflated central cylinder surrounds a large heterogeneous medulla, the large celled, succulent core of which has dried up and has been trimmed away by the ants. In other words, these structures are quite distinct morphologically from the myrmeeodomatia of the Physocladae, and resemble those of the Ethiopian species of Cuviera and Plectronia." Menozzi (1927) has recently published a few notes on the domatia of C. alliodora (cited as gerascanthus) and their ant-tenants, collected by H. Schmitt in the vicinity of San Jose, Costa Rica. He figures the domatia and describes the coccids as probably belonging to the genus Cryptostigma, the ants as Crematogaster brcmspinosa Mayr, Cryp- tocerus setulifer Emery and Azteca pittieri Forel. Standley (1924, 1928) gives a brief but excellent description of C. alliodora. He finds it to be one of the common trees of Mexico and Central America, ranging as far north as Sinaloa, and that "the forks of the young twigs are almost always enlarged by hollow swellings, which afford shelter for fierce ants, hence the name "hormiguero." The fruit is edible. A decoction of the leaves is employed as a tonic and stimulant, especially in the case of catarrh and afflictions of the lungs, and an ointment made with the pulverized seeds has been used in the West Indies as a remedy for cutaneous diseases. The fresh bark is reported to have an odor suggestive of garlic." x The recent study of the Cordias by Chodat, Vischer and Carisso is so much more extensive than that of previous writers and so significant in connection with my own observations that it must be considered in detail. These authors investigated several species in Paraguay (C. glabrata var. orbicularis, Hasslcriana, Chaniissoniana and longituba and two species, salicifolia and chaeocnsis, which belong to another ■The economic value of the tree is indicated by the number of local names which it bears in various parts of its range. These are cited by Standley as "bojon", "bojon bianco", "bojon prieto" (Tabasco); "tambor" (Michoacan) ; "hormiguero" (Michoacan, Guerrero, Oaxaca) ; "amapa prieta" (Sinaloa); "palo de rosa" (Oaxaca, Cuba, Porto Rico); "palo Maria" (Guer- rero) ; "laurel" (Panama, Costa Rica, El Salvador, Guatemala, Honduras) ; "Solera" (Colombia) ; "laurel macho" (Nicaragua); "capa prieta" (Porto Rico, Cuba); "varea", "capa voja" (Cuba); "canjara", "pardillo" (Venezuela); "arbol del ajo" (Peru); "laurel bianco" (El Salvador); "canalete" (Colombia). 18 bulletin: museum of comparative zoology group of forest Cordias related to the Physocladse). As gerascanthus and alliodora were not found in that country, they resorted to herb- arium material for a knowledge of their peculiarities. For many ecological and morphological details of purely botanical interest the reader may be referred to the first section of the paper by Chodat and Vischer, but the second section, on the myrmeeophily of the Cordias of the gerascanthus group, calls for fuller discussion. The authors state positively that the cauline swellings are not preformed structures, like those of the Physocladse, but true galls, which owe their inception to infection by a Chalcidid of the genus Eurytoma, according to C. Ferriere's identification. Apparently, only the egg, larva, and pupa of the gall-maker were obtained. In C. gerascanthus Jacq. (that is alliodora) "the beginning of the infection occurs at the base of the inflorescence or at one of the secondary forks of the latter." And the following remark is added: "We have traced a similar development of this gall in the plant from Guatemala. We were able to ascertain the beginnings of the development of the larva and its morphogenetic action which results in a biomorphosis of rather large dimension." Their Fig. 322 shows a longitudinal section of a young gall with the Eurytoma egg at the base of a feeble inflorescence of C. gerascanthus. Their Fig. 328 is an enlarged sketch of portions of such a gall contain- ing larva?. Figs. 314a and b, representing similar conditions in C. glabrata and longituba, are quite unlike the typical cauline swellings of alliodora. Moreover, the authors confess (p. 179) that they did not follow the ulterior development of the structures in the Paraguayan species. The exit hole of the adult Eurytoma is supposed to form the opening through which the ants enter the gall, but no attention is paid to the relatively enormous increase in size of the structure after the minute Chalcidid has deserted it, and neither text nor figures give any clear and convincing account of the eventual developments. The authors do, indeed, describe and figure the fully-formed swelling but they say nothing about the large coccids which were probably present in the specimens they examined and had so vividly impressed Beccari and Townsend. The Genevan botanists figure the convoluted carton mass in the cavity of the fully formed swelling and find it to consist of the pollen and stellate and other hairs of the Cordia, starch grains from the pith, filamentous fungi and bacteria allied to Leptothrix. This led them to quote the sentence which I have cited from Ruiz and Pa von and to conclude as follows: "We may therefore regard these structures (i.e. the convoluted masses of carton) as fabricated by the ants themselves with materials from at least two sources: first, the wheeler: neotropical ant-plants and their ants 19 pollen of the innumerable flowers, second, the agglomerated fragments of lacerated leaves or flowers; third, fungi, perhaps intentionally introduced by the ants (acting as mycetophagous horticultural insects?)." The general results of their study are summarized by the authors in the following paragraphs : "Thus our investigations establish a new theory of the myrmeco- phily of Cordia, based on incontestable facts. Observations made by an entomologist in the field will fortunately complete the sketch which we have given of the curious phenomenon, but in the meantime, till these observations are forthcoming, we would call the attention of biologists to the following points: "Throughout the entire range of species of the section Gerascanthus, from Mexico to Paraguay and from the Guianas to Eastern Peru and Bolivia, we have demonstrated, either in the field (Paraguay) or by examination of herbarium material, the general infection of these plants by ants of the genera Azteca and Pseudomyrma, which estab- lish their formicaries in these empty galls with materials taken from the host plant. We are not therefore concerned with ants that protect the plants from the leaf -cutters (Atta sexdens), according to the theories of Belt, Mueller and Schimper, since they attack, not the glands of the plant as if they were prepared for the benefit of the ants, as in the case of Cecropia, but essential organs, the pollen and paren- chyma of the leaves. "We fail to see any advantage these trees might derive from the presence of the ants. Their habitual presence on certain species of Cordia clearly shows that these plants which are so widely distributed and so abundant, suffer in no wise essentially from this attack and symbiosis, since it does not jeopardize the existence of the Cordias and is profitable only to the ants. In so far as the Cordias are con- cerned, there is merely a biomorphogenic reaction." Chodat and Vischer thought they found confirmation of their general conclusions in their study of the large thorns of the Paraguayan Acacia cavenia, which will be discussed in connection with the Central American Acacias (p. 116), but Fiebrig (1909) had previously shown that the cavenia thorns are originally inhabited by Lepidopteran larvae (Tineids). It is difficult to understand why Chodat and Vischer should have regarded their theory as "new." Myrmecologists have long been familiar with the fact that ants are very fond of nesting in the aban- doned galls of the most diverse plants, and if the cauline swellings of the Cordias of the Gerascanthus group are nothing but galls, these plants obviously cannot be regarded as myrmecophytes. I trust that 20 bulletin: museum of comparative zoology the following observations will demonstrate that the Genevan botan- ists have reached erroneous conclusions from insufficient data. I found C. alliodora to be a common tree on the Pacific side of the Panama Canal Zone and less abundant on the Atlantic side near Colon. There are many specimens of it on Barro Colorado Island, in Gatun Lake. From Frijoles to Ancon it is often a common component of the second growth jungle, or thickets, and in the clearings, but usually avoids moist spots and seems to show a preference for the slopes of hills. It comes into flower during the last days of February and con- tinues to bloom profusely till about the last of March. During this portion of the dry season the large compact racemes of small white blossoms make the trees conspicuous objects in the landscape (Plate 2). Seedlings and young trees of all sizes can often be found singly or in colonies, especially about clearings and along road-sides, so that the plant can be readily studied in all stages. The largest specimens attain a height of 30 or 60 feet, but flowers are not produced till the tree is about 10 or 15 feet high. While young (below about 4 to 6 feet) it is usually very symmetrical, with the branches coming off in regular whorls at intervals along the straight, slender trunk, so that in this stage it somewhat resembles adult specimens of C. nodosa. Later the branches vary much more in length and direction and are less horizon- tal. Eventually the crown of foliage may be either irregularly pyrami- dal or, especially when growing in the open, more diffuse and spreading. The trunk and branches are slender and graceful, with moderately smooth, gray bark. The ovate coriaceous leaves are two to four inches long and grayish green, with rough margins. There is considerable variation, however, in the texture and surface of the leaves. The flowers have a strong odor, somewhat like that of decayed urine. They soon turn brown and persist for some time, often till the middle of April, but later fall and the same is true of the stems of the inflorescence though its base, which has a well-developed swelling, or domatium, may remain behind as a dead and dry structure for at least a year. Those who may not care to study the Cordias in the Panamanian jungles will find a number of fine specimens on the hospital grounds, about the reservoirs and in the gardens of private dwellings at Ancon and Balboa. An unusually fine tree nearly 40 ft. high, on the slope of the lower reservoir in Ancon, is shown in Plate 1. An examination of fully developed trees shows that there is almost invariably an ant-inhabited domatium at each node and that the swellings grow larger successively the nearer they are to the bases of the branches, but the stoutest branches and the trunk exhibit little or wheeler: neotropical ant-plants and their ants 21 no enlargement in the corresponding regions. Here the domatia per- sist, nevertheless, but are concealed by a normal and very considerable growth in the thickness of the wood. These masked cauline swellings will be discussed later. It is a singular fact that the adult C. alliodora trees lose their leaves during the rainy season when all the other trees of the Panamanian jungle are in full foliage. During July and August the bare trunks and branches stand out as if dead among the dense green foliage of the other trees and the regular arrangement of the domatial swellings at the insertions of the branches becomes con- spicuous. These trees could thus be located with the field glasses among the tree-tops visible from the laboratories at Ancon and Barro Colorado Island. My attention, like that of Chodat and his collaborators, was at first directed to the inflorescences, by finding distinct elongate thickenings of some of the small flower-stems, and I, too, at first took these thick- enings to be the initial stages in the formation of the ant-inhabited cauline swellings. In the thickenings I also occasionally found minute maggot-like larvae but did not succeed in rearing the adult insects. They were Hymenopterous and very probably the larva? of the Eury- tomid observed by the Genevan botanists, or of some allied species. But most of the enlargements, which are only 2 or 3 mm. in diameter, contain no traces of eggs or larvae and are filled with a uniform and un- disturbed mass of brown pith. I am certain, therefore, that they are not galls but merely occasional preformed thickenings of the flower stems, in which the Eurytomids lay their eggs. In other words, these thickenings are strictly limited structures which precede the infection and are not produced by it. The Eurytomid (?) larvae simply feed on the pith which happens to be more abundant in the thickenings than in other portions of the flower stems. That these thickenings do not become the true nodal or cauline swellings inhabited by the ants is proved by the fact that they wither and drop off after flowering and cannot therefore produce persistent leaf-bearing branches. True woody galls are, however, occasionally produced on the twigs of the tree by some unidentified insect. One vigorous young tree about 10 ft. high observed Aug. 2, 1924 on Barro Colorado Island had many of these galls, which were regular, ovoidal thickenings of the twigs below the true domatia, quite unlike them in form and about 2 to 3 cm. long and 1 cm. in diameter. They were hard and woody and contained winding passages made by some boring larva. Many of these galls were inhabited by portions of the same Azteca longiceps colony that occupied the domatia on the same tree. 22 bulletin: museum of comparative zoology In order to ascertain the origin of the cauline swellings it is necessary to investigate the seedlings and young Cordias and the suckers that often grow up from the roots of larger trees that have been felled. These juvenile stages present a very different picture from that de- scribed by Chodat and Vischer. The plants are green throughout and actively growing and, as I have stated, very symmetrical in the ar- rangement and length of their few branches and nodes. Each of the latter is regularly swollen and turbinate and forms a rather thin- walled, green capsule closed on all sides and varying according to its age from 5 to 20 mm. in diameter. The delicate remnants of the pith form an even layer over the wall of its large cavity, which contains no traces of any insect parasite. Nor does the great majority of juvenile trees or suckers contain any ants till they reach a height of about three to five feet. The swellings are so perfectly regular in their ar- rangement and in position so comparable to those of the Cordias of the Physoclada group and so constantly present, except in the youngest seedlings less than a foot in height and with only the first whorl of leaves, that no botanist and certainly no entomologist, could possibly regard them as galls. Very occasionally there may be no swelling at a node where it might be expected to appear, but this sometimes happens also in the Physocladse, and such inhibitions of development do not invalidate the general conclusion that the domatia of C. dlliodora are quite as certainly preformed structures as those of C. nodosa. Of course, the crucial demonstration that the domatia are preformed can come only from growing the plant from seed under controlled condi- tions. I made an attempt to accomplish this with seeds sent to Boston by Mr. Zetek, but they failed to germinate in the hot houses of the Bussey Institution, probably because they were sterile. Except in the domatia at the very base of the inflorescence, which, as previously stated, may persist and dry up when the latter falls off, there is a gradual growth in the thickness of the woody walls and in the size of the enclosed cavity. The series of photographs (Plates 3, 4, 5) show this increase very clearly. The ants perforate and enter the domatia very soon after their walls begin to lignify. I have not been able to follow the details of the invasion, although I have frequently found single young dealated females of various species and notably of Aztcca longiceps Emery, either alone or with their first brood of larvse, in the swellings. The perforation or perforations — for there may be several — are always made in the thinner portion of the wall below the node, but there is no regularity in their position. In many cases the opening made by the entering queen closes by growth of the wheeler: neotropical ant-plants and their ants 23 plant tissues and has to be reopened by the first brood of workers. The continued growth of the domatium after its occupation must be due to the constant irritation produced either by the ants or by the numerous Coccids which attach themselves to the walls of the cavity and sink their delicate mouthparts into the plant tissues. That the Coccids may be the more potent irritants seems to be indicated by the conditions in the various Aphid and Psyllid galls of temperate regions and the Coccid galls of Australia. In the case of C. alliodora, the Coccids may be responsible not only for the irregular shapes assumed by many of the domatia in their later stages, but also for the unequal vigor and growth of the branches at the nodes and the general asym- metry of the older trees (Plate 6, Fig. b). That the growth of the domatia does not continue indefinitely is shown in longitudinal sections of the nodal regions of the trunk and larger branches of old trees. The cavity ceases to enlarge when it reaches about the size shown in Plate 6, Fig. a, but the layers of xylem in its wall increase so enormously that the external swelling is obliterated. Concomitantly with this growth in the xylem the perforations or entrances to the cavity develop as long tubular galleries which traverse the whole layer of wood. In the section represented in Plate 7, Fig. b, which is slightly less than natural size, there were seven of these galleries which radiated from the chamber and opened on the surface of the bark at points several inches apart. Although even at this stage the cavities may still be inhabited by ants, the Coccids have all disappeared, probably because their food-supply has been completely shut off by the development of the very thick layer of wood between the cavity and the cambium. The regular development of the swellings, or domatia in C. alliodora and other Cordias with such preformed structures thus presents a very interesting problem to the plant anatomist interested in phylogeny. Attention may be called in this connection to similar structures in at least one other plant in a very different genus, all the other species of which have stems of the normal unswollen type. This is the Poly- gonaceous genus Eriogonum, which comprises about 100 species in the United States west of the Mississippi. One, however, E. inflatum Torre, has hollow, fusiform swellings at the upper ends of the inter- nodes of the stems and branches. I have observed this plant at Palm Springs, California, in the Mojave Desert at the foot of the San Jacinto Mountains. It is one of the few perennial species of the genus, according to Tidestrom (1925), who cites it as belonging to the "desert areas and hillsides of the Covillae and Artemisia belts" in 24 bulletin: museum of comparative zoology Southwestern Utah, Colorado, Nevada, Arizona and California. The swellings are not inhabited by ants, because all the Formicidse in its desert environment are earth nesting forms. But there is no doubt in my mind that if the plant were to invade the tropics, certain species of stem-inhabiting ants would at once take up their dwelling in its inflations. Under these circumstances the plant would become a regular myrmecophyte like C. alliodora. The following is a list of the ants that have been found associated with C. alliodora in Mexico, Central America, Peru and Bolivia: ( 1) Ectatomma ruidum Roger. Foraging on trunk and foliage. Ancon, C.Z. ( 2) Ectatomma tuberculatum Oliv. Foraging on trunk and foliage. Barro Colorado Is. C. Z. ( 3) Ectatomma (Gnamptogenys) sulcatum F. Sm. On trunk. Barro Colorado Is. C. Z. ( 4) Neoponera crenata Roger var. m&sta Mayr. In domatia. Que- brada de Oro and Barro Colorado Is. C. Z. ( 5) Pseudomyrma alliodoroe sp. nov. In domatia. Ancon, C. Z. ( 6) Pseudomyrma belli Emery subsp. fulvescens Emery. Types taken by Beccari from domatia. Guatemala. ( 7) Pseudomyrma excavata Mayr, var. flaviventris Forel. In domatia. Barro Colorado Is. C. Z. ( 8) Pseudomyrma gracilis Fabr. In domatia. Red Tank, C. Z. In domatia of C. alliodora var. bolivianat Riberalta, Bolivia (W. M. Mann). ( 9) Pseudomyrma gracilis var. bicolor Guerin. In domatia. Red Tank, Gamboa and Quebrada de Oro, C. Z. (10) Pseudomyrma sericea Mayr var. ita Forel. In domatia, Ancon, C.Z. ' (11) Pseudomyrma sericea var. cordia? Forel. In domatia of C. alliodora var. boliviana? Ivon Beni & Huachi Beni, Bolivia (W. M. Mann); Bolivia (Bang); Eastern Peru (Spruce). (12) Pheidole radozskotcslcii Mayr, var. In domatia. Ancon, C. Z. (13) Crematogaster acuta F. In domatia. Barro Colorado Is. C. Z. (14) Crematogaster (Orthocrema) brevispinosa Mayr. In domatia. San Jose, Costa Rica (H. Schmitt). (15) Crematogaster (Orthocrema) brevispinosa subsp. tumulifera Forel. In domatia. Red Tank, C. Z. (16) Crematogaster (Orthocrema) limata F. Sm. var. In domatia. Gamboa, C. Z. wheeler: neotropical ant-plants and their ants 25 Crcmatogastcr (Orthocrema) limata subsp. parabiotica Forel. In domatia. Red Tank, C. Z. Crcmatogastcr (Orthocrema) limata subsp. ludio Forel. In domatia of C. alliodora var. bolivianat Huachi Beni, Bolivia (W. M. Mann). Crcmatogastcr (Orthocrema) sumichrasti Mayr. In domatia. Quebrada de Oro, C. Z. Crcmatogastcr (Orthocrema) virgula Forel. In domatia. Red Tank, C. Z. Solenopsis hermione Wheeler. In domatia. Gamboa, C. Z. Solenopsis laiviceps Mayr. In domatia. Barro Colorado Is. C. Z. Solenopsis picea Emery. In domatia of C. alliodora var. boliviana? Isiamas, Bolivia (W. M. Mann). Solenopsis zetehi Wheeler. In domatia. Red Tank, C. Z. Leptothorax (Goniothorax) echinatinodis Forel subsp. cordincola subsp. nov. In domatia. Red Tank, C. Z. Wasmannia auropunctata Roger var. nigricans Emery. In do- matia. Barro Colorado Is. C. Z. Cryptoccrus (Cyathocephalm) sctulifer Emery. In domatia. Ancon, C. Z.; San Jose, Costa Riea (H. Schmidt). Cryptoccrus (Cyathoccphalus) pollens Klug var. porram var. nov. In domatia. Frijoles, Red Tank and Quebrada de Oro, C. Z. Atta sexdens L. On foliage. Aneon, C. Z. Dolichoderus (Monads) bispinosus Oliv. In domatia. Red Tank, C. Z. Dolichoderus (Hypoclinea) championi Forel subsp. trinidadensis Forel var. tamiatus Forel. In domatia. Frijoles, C. Z. Azteca fasciata Emery subsp. losta Wheeler. In domatia. Gamboa, C. Z. (a single female). Azteca foreli Emery var. xysticola Forel. Running on bark and nesting in trunk. Ancon, C. Z. Azteca instabilis Emery var. Nesting in trunk. Barro Colorado Island, C. Z. Azteca bicolor Emery var. Incipient colony in domatium. Ancon, C. Z. Azteca longiceps Emery. In domatia. Ancon, Red Tank, Frijoles, Las Cascades, Barro Colorado Is. Agua Clara Reservoir, Gam- boa, Corozal, etc. C. Z. Azteca longiceps subsp. balboas subsp. nov. In domatium. Balboa, C. Z. A single dealated female. 26 bulletin: museum of comparative zoology (38) Azteca longiceps subsp. cordincola Forel. In "galls" of Cordia. Bolivia (Chodat). In domatia of C. alliodora var. boliviano,? Huachi Beni, Bolivia (W. M. Mann) (39) Azteca longiceps subsp. patruelis Forel. In domatia. Cualata, Colima, Mexico (C. H. T. Townsend) (40) Azteca pittieri Forel. In domatia. Tumba Muerta, Panama ; Red Tank, C. Z. San Jose, Costa Rica (H. Schmitt). (41) Azteca pittieri Forel var. emarginatisquamis Forel. In domatia. Costa Rica (Pittier). (42) Azteca trigona Emery. In domatia. Ancon and Las Cascades, C. Z. (43) Azteca velox Forel. In domatia. Ancon and Marajal, near Colon, C. Z. (44) Tapinoma canalis Wheeler. In domatia. Barro Colorado Is. C, Z. (45) Brachymyrmex hceri Forel var. obscurior Forel. In domatia. Barro Colorado Is. C. Z. (46) Camponotus (Tan&myrmex) coruscus F. Sm. Exploring foliage. Ancon, C. Z. (47) Camponotus (Myrmosphincta) Q-guttatus Fabr. var. bimaculatus F. Smith. In domatia. Barro Colorado Is. C. Z. (48) Camponotus (X comyrmamblys) novogrcnadensis Mayr. In doma- tia. Quebrada de Oro, C. Z. (with Microdon puparia). (49) Camponotus (Myrmobrachys) canescens Mayr. In domatia. Barro Colorado Is. C. Z. (50) Camponotus (Myrmobrachys) brettesi Forel. In domatia. Ancon C. Z. (51) Camponotus (Myrmobrachys) lindigi Forel. Exploring foliage. Ancon, C. Z. (52) Camponotus (Myrmobrachys) brevis Forel. In domatia. Red Tank, Gamboa, Frijoles, Las Cascades and Barro Colorado Is. C. Z. (53) Campo?wtus (Myrmocladcecus) bidens Mayr. In domatia. Red Tank, C. Z. (54) Paratrechina longicornis Latr. Exploring foliage. Ancon, C. Z. Of the 54 different forms in this list 44 were found nesting in the domatia; the remaining 10 were either nesting in the trunk (Azteca xysticola and instabilis) or in the ground (the species of Ectatomma, Atta, Paratrechina and some species of Camponotus) and merely visited the foliage to attend Aphids or Coccids or to forage for insects. Atta sexdens was not seen to cut the leaves, which seem not to be in- wheeler: neotropical ant-plants and their ants 27 jured by this ant, probably on account of their coarse texture. The great majority of the domatia tenants occur also in dead twigs of a great variety of trees and shrubs. Probably only four of the species listed, namely, Azteca longiceps and its subspecies, A. pittieri and its var. emarginatisquamis, Pseudomyrma sericea and its varieties ita and cordice, and Ps. attiodorce, are to be regarded as obligate tenants of the plant. Of these A. longiceps is the most abundant and occurs in about 85% of the cauline swellings. Forel cites Pseudomyrma chodati as living in "galls" of C. longitvha in Paraguay and Ps. sericea var. cordice from an undetermined Cordia. If this plant belongs to the Geraseanthus section we may say that its members are inhabited by at least 60 different species, subspecies and varieties of ants. Indeed, the number is probably much greater, because the ants inhabiting these Cordias have not been intensively collected, except in a portion of the Panamanian region. For the purpose of studying the ants of C. alliodora Mr. James Zetek and I adopted a method, which we also employed successfully, with obvious modifications, in dealing with other myrmecophytes (Tri- plaris, Acacia, Cecropia, Clerodendron, Tillandsia). We either cut down the tree, or when this was impracticable, lopped off large branches. Then with a pair of strong pruning scissors we cut out the cauline swellings and carried them in cloth bags to the laboratory, where they were placed in a large jar. Some chloroform was poured on the bags and the jar covered till the insects were asphyxiated. The nodes could then be cut open and their contents examined at leisure. We found that few of the ants left their nests to die in the bags and that the swellings, even when they were inhabited by different species, contained all or nearly all of their regular inhabitants. The preliminary work of ascertaining the qualitative composition of the alliodora bioccenose was so time-consuming that a quantitative or statistical study of the various species could not be attempted. It is to be hoped that some future student will feel inclined to undertake such an in- vestigation at the new tropical laboratory on Barro Colorado Island. A number of the alliodora ants, especially those of the genera Crematogaster, Leptothorax, Cryptocerus, Tapinoma and Campono- tus, are very sporadic, occurring in only a few of the swellings on a tree or branch. Azteca longiceps is certainly the common and dominant tenant in nearly all the localities in which I collected. It usually occupies most or all of the swellings, especially those at the bases of the branches, whereas the sporadic species inhabit by preference the terminal and especially the dead and dried swellings that bore the 28 bulletin: museum of comparative zoology inflorescences of the previous dry season. Not only A. longiceps and pittieri and the varieties of Pseudomyrma sericea but also several of the other forms keep living Coccids in their nest-cavities. I here insert a fuller description of the habits of A. longiceps as the most typical of the alliodora tenants and append brief notes on some of the other ants. Unlike the larger aggressive Aztecas (trigona, velox, foreli, instabilis, etc.) which either make large pendent carton nests on various trees or form compact and populous colonies in their trunks, longiceps is a small, timid and rather lethargic ant. This is indicated both by its toleration of other ant-tenants on the same tree and by the fact that I have sometimes cut up Cordias for hours without being bitten more than half a dozen times by the larger workers. The longiceps inhabit- ants of all the domatia on a tree constitute a single polycladic colony, which keeps growing and spreading by successive occupation of the new swellings as fast as they attain the proper size on the developing branches. During March and April the nests contain much brood in all stages together with many males and winged females. The domatial cavities are lined with a thin layer of brownish or blackish substance and contain a black or dark brown mass of carton made up of a net- work of traveculse like those constructed by many other Aztecas that nest in plant cavities. This structure, shown in Plates 7 and 8, was seen by Beccari and Chodat and Vischer, but in their figures it is repre- sented as grosser or more massive. It consists of very finely and uni- formly triturated and agglutinated particles of wood and pith. I have failed to detect in it any pollen-grains, leaf-fragments or stellate hairs but would not deny that such substances may, perhaps, be occasionally employed by the ants in the confection of the mass. It is obviously a kind of scaffolding which subdivides the original cavity of the doma- tium into smaller compartments and galleries in which the brood can be spread out and more easily cared for. The mass can be readily re- moved in its entirety because it is rather feebly attached to the walls of the cavity. Chodat's and Vischer's contention that the ants, "devorent une partie des feuilles et recoltent le pollen" is highly improbable. I have never seen the Aztecas visiting the flowers and they certainly do not devour the leaves. But even if this were true, and if the carton were made of leaf material as these authors maintain, the combined mass of carton in all the domatia on a tree would be too small to repre- sent any serious damage to the plant. In the spaces surrounding the mass of carton and sometimes almost covering the walls of the cavity are the numerous Coccids among wheeler: neotropical ant-plants and their ants 29 which at least three kinds or species may be readily distinguished. The majority are flat Lecanoid forms of a pinkish color and varying con- siderably in size. Among them may be found small snow-white Pseudococci, either singly or in clusters and several large subglobular shining black or red forms belonging to three species of the genus Cryptostigma. These Coccids suggest interesting problems and reflections. They are present in such numbers that they must provide the ants with a copious supply of honey-dew. That the large subglobular forms (Cryptostigma) breed in the domatia is indicated by the fact that they are often found to be filled with eggs and owing to their size are quite unable to escape to the surface of the plant through the tenuous open- ings in the walls of the domatia. But whether the coccid colonies are originally established by young individuals that crawl into the swellings from the surface of the plant or are carried in by the ants, cannot be decided without further observation. Judging from what is known of some other ants (Lasius species, Iridomyrmex humilis, etc.), the latter alternative would seem to be the more probable. I have seen what I take to be the male pupae of one of the large Cryptostigma species en- closed in peculiar flattened, bivalve-like cases, embedded in the central mass of carton. The Pseudococci are often destroyed by the larvae of a small Chalcidid of the genus Blepyrus very much like B. tachigalice Brues which I found infesting Pscudococcus brevipes in the petiolar en- largements of Tachigalia panieidata Aublet in British Guiana. There is also in the cavity of each domatium occupied by A. longi- ceps another singular object which has been overlooked by previous observers. The funnel-shaped lower end of the cavity is filled with a small conical plug of moist substance, which can be readily removed as a coherent mass and on examination proves to have a very complex structure, consisting of the ejected infrabuccal pellets of the ants, moulds and innumerable bacteria and Nematode worms. Its more liquid portion is probably the faeces of the ants and such honey-dew from the Coccids as happens to drain down the walls of the cavity and has not been intercepted and imbibed at its source. We may therefore regard the lowermost funnel-shaped end of the domatial cavity as a veritable public latrine or cess-pool. The Nematodes have been studied by Dr. Cobb who informs me that they are unusual from the taxonomic point of view. The moulds and bacteria which flourish in the faecal medium of the latrines may afford an interesting study for some future investigator. In Mexico the subsp. patruelis and in Bolivia the subsp. cordincola 30 bulletin: museum of comparative zoology seem to replace the typical A. longiceps as the obligate ants of C. allio- dora. But even in Panama the typical longiceps may be replaced by A. pittieri, an ant of very similar appearance and habits. I found this to be the case in a small piece of jungle on the Tumba Muerta Road, near Las Sabanas. According to my observations, Pseudomyrma sericea var. ita is much less important as a member of the alliodora bioccenose. Its colonies are small and usually occupy only a few of the domatia on trees infested with A. longiceps. The same is true of Ps. gracilis and its var. bicolor which are more frequently found in hollow twigs of various trees and shrubs. Ps. alliodorae is a timid form of rather spora- dic occurrence. The older accounts of Ruiz and Pavon and Spruce seem to imply that Ps. sericea or other species of the same genus may be abundant and more formidable tenants of the Cordias in certain parts of South America. The species of Cryptocerus are sluggish, cowardly and harmless. Both of the forms cited above, sehdifer and pollens var. porrasi may occupy occasional swellings on trees infested with other ants. They belong to the subgenus Cyathocephalus, the females and soldiers of which have the top of the head peculiarly modified in the form of a large elliptical or suborbicular dish. A swelling occupied by Crypto- cerus can be at once recognized by its entrance hole, which unlike that made by the Azteeas and Pseudomyrmas, is large and regularly elliptical instead of being small and round. The mother queen of the incipient colony or in older colonies one of the soldiers, constantly stands guard at the entrance and occludes it with the dish-shaped top of her head. This behavior is exactly like that of Colobopsis, except that in the ants of this subgenus, the portions of the head employed as a door are the truncated, orbicular front and cheeks. In the mother queen and older soldiers of Cryptocerus colonies the cephalic dish has been so persistently used in the manner described, that its concavity is often found thickly incrusted with grayish green foreign matter and thus comes to resemble the dull gray lichen or alga covered bark of the Cordia. The two species of Cryptocerus, like several other ants enumerated in the list on p. 25, are merely inquilines which often nest in the dead twigs and branches of other trees and shrubs. That Cordia alliodora can derive little protection from the numerous ants which it harbors, is obvious from my account of their disposition and behavior. There is further evidence of this inefficiency in the great number of insects and other organisms that infest the foliage and flowers of the plant. Although Mr. Zetek and I devoted much attention to these forms, we were soon convinced that it would require wheeler: neotropical ant-plants and their ants 31 many months or even years to gain an adequate knowledge of the alliodora bioccenose and the interrelationships of its numerous com- ponents even in so limited an area as the Canal Zone. The following list of species hitherto observed, however, with notes on some of the more interesting forms, will constitute a sufficiently formidable re- buttal of the argument that C. alliodora would probably perish in the struggle for existence if it failed to attract and provide quarters for battalions of ants. Lepidoptera. At least six different species of moth caterpillars feed on the leaves of C. alliodora and some of them are rather destructive. One is a small leaf-miner of which I have seen only the small blister- like feeding-spots. Of another moth I have seen only the beautiful yellowish, regularly net-like cocoon spun in a folded leaf and contain- ing an empty chrysalis. Three slender green caterpillars belonging to as many different species also remain to be reared and identified by some future observer. One of these larvae which is fairly abundant bites a big hole in the wall of a young green domatium and hides in its cavity during the day. At night it eats the terminal leaves and spins their remains together about the domatium, leaving its frass among them. This untidy insect is very destructive to the terminal shoots of the Cordia. In a domatium containing one of these larva? I found two small white Hymenopterous pupa? but did not succeed in rearing the adult parasites. The numerous caterpillars of a sixth species are about an inch long, chocolate brown with a pale mid-dorsal streak. They have been reared by Mr. Zetek who sent me specimens and photo- graphs (Plate 9) of the cocoon, caterpillar and its method of feeding and hiding on the Cordia leaves. The adult moth, which is silvery white with black markings, is a Pyralid and was identified by Mr. W. Schauss as Conchylodes salamisalis Druce. Its life history is sketched in the following note contributed by Mr. Zetek: "The larva makes a sort of silken retreat at the base of the upper surface of the leaf by binding threads crosswise, thus forming a triangular cavity in which it can lie concealed. There is only one larva to a leaf. On one small plant, about five feet tall I saw 15 such larva?. When ready to pupate, it spins a capsule 7/8 in. long by 5/6 in. in diameter, rounded at both ends and so well sealed that it is difficult to detect the sutures. After completing its cocoon it takes the larva about 36 hours to become a chrysalis. During this time, especially if the case be disturbed, the larva moves so violently inside, as actually to make the cocoon bound up an inch. The pupal stage last 12 days. Adults emerged June 12, 1923." During 1924 I found Conchylodes caterpillars on 32 bulletin: museum of comparative zoology many young Cordias at Ancon, Red Tank and Gamboa. During June the caterpillars were mature and ready to pupate and by the middle of July there were many young caterpillars of the next brood. Probably there are several generations on the young plants during the course of the year. The adult Cordias are immune from their attack during the rainy season, because they are leafless at that time. Diptera. Numerous flies may be observed on the leaves of the young Cordias but are probably mostly chance visitors that alight on any low vegetation. Among those captured at Ancon and on Barro Colorado I recognized 3 species of Stratiomyids, 2 Syrphids, 1 Doli- chopodid, 1 Micropezid, 2 Ortalids and 3 Muscids. The Cordia leaves are often dotted with small, spherical, densely pilose galls, which con- tain orange-colored Cecidomyid larvae. I did not succeed in rearing the adults. More interesting is a species of Microdon, which has been described by Dr. Mann (1928) as M. wheeleri, since it lives with one of the ants in the domatia. March 10 I found at Red Tank, C. Z. in a Cordia swelling inhabited by Crematogaster (Orthocrema) brevispinosa var. tumulifera four bright yellow puparia, which were smooth and cylindrical and quite unlike any Microdon puparia known to me. They were carefully kept in a Petri dish till March 27, when two of the flies emerged and proved to belong to a very small species, about 7 mm. long. On emerging the hairs on the thoracic dorsum and sides and dorsum of the abdominal segments were conspicuously golden yellow and to all appearances true trichomes, but 24 hours later they had turned black. The other pair emerged March 28 and were chloro- formed in the golden phase. They proved to be females whereas the first pair were males, so that I am unable to decide whether the females also blacken like the males. This is important in connection with Mann's description of the female. Unfortunately I failed to preserve the domatium in which the Microdon puparia were found although I kept all the ants and Coccids. The latter belonged to one of the species of Cryptostigma so common in the cauline swellings, especiallly when they are inhabited by Azteca longiceps. Perhaps one of the openings in the wall of the swellings may have been large enough to admit an ovipositing Microdon, but I failed to notice such an opening and am therefore unable to throw any light on how the Microdon larvae get into or how the flies escape from the domatium. Probably the phase with the golden trichomes just after emergence is in some way connected with securing a temporary immunity of the fly from the attacks of the ants, and perhaps the latter enlarge their nest- entrances to let the flies out, but this is pure speculation and is merely wheeler: neotropical ant-plants and their ants 33 set down here for the benefit of someone who may be fortunate enough to happen on this rare and singular insect again. The problem of the food of the M. wheeleri larvse is also, of course, unsolved. Donisthorpe (1912, 1923) has shown that the larva of the common European M. mutabilis feeds on the infrabuccal pellets which the ants cast out in their nests, and no doubt our North American Microdon larvae have the same diet, but that the tropical Microdons may have very different habits is shown by Borgmeier (1923), who has recently found the larvae of a Brazilian species devouring the Coccids (Pseudo- coccus inquilinus) in the nests of the fire ant (Solenopsis scetissima var. picea). Perhaps M. wheeleri feeds on the coccids in the Cordia domatia. Hymenoptera. The following species of this order have very diverse relations to the Cordia and its inhabitants. (1) A single unidentified Tenthredinid taken on the foliage at Ancon. (2) Dicrophrys sp. (C. T. Brues det.) An Ichneumonid taken occa- sionally on the foliage of young .Cordias at Ancon and possibly a parasite of one of the caterpillars enumerated above. (3) Eurytoma sp. (?) A small larva, apparently related to the one described and figured by Chodat and Vischer, was found living in the swollen stems of the flower panicles. (4) Blepyrus sp. Living as an entoparasite of Pseudococcus in the cauline swellings inhabited by Azteca longieeps. I saw only the empty puparia but they were not uncommon and are, I am inclined to believe, identical with those of B. tachygalice Brues, which I found in the same Coccids living with the social beetle Coccidotrophus socialis in the petioles of Tachigalia paniculata of British Guiana (see my paper of 1921). (5) A Pteromalid (Brues det.) bred from flowers at Red Tank, C. Z. (6 and 7) At Ancon I found two small mud nests attached to the twigs of Cordia and from them reared two solitary wasps. One of them proved to be Eumenes infernalis Sauss. (J. Bequaert det.), the other a Sceliphron. The latter was so nearly destroyed by house-ants entering the breeding cage that more precise identification was impossible. (8) March 28 at Frijoles I found a nest of a very interesting social wasp, Polistclla picteti var. wheeleri Bequaert, among the leaves of a Cordia about 15 feet high. The nest was about 6 inches long and consisted of four small, rather irregular, pale gray paper combs partly enveloped by the leaves to which they were broadly attached. The wasps made not the slightest attempt to sting but retreated into 34 bulletin: museum of comparative zoology their nest. The structure was very similar to that figured by Ducke (1910, p. 473, Fig. 2) for Polistdla picteti var. bella v. Ihering. Con- cerning an allied species P. emortualis Sauss. of the Guianas and Brazil, he writes: "It is myrmeeophilous. I have never found it alone but always in the company of ants of the genus Dolichoderus. The nests are very similar to those of the ants mentioned, built on the leaves of the same small branch of the tree whose other leaves harbor the nests of the latter. I have even seen a colony of nests of the wasp and of the ant closely associated on the same leaf. It is surprising to note that the ants are very aggressive, whereas the wasps, though furnished with stings take refuge in the interior of the nest when it is touched." That P. picteti may also be myrmeeophilous is indicated by the fact that all the swellings of the Cordia on which the nest occurred were occupied by vigorous colonies of Azteca longiceps. (9) Ccratina sp. A beautiful metallic blue species nesting in a dead Cordia branch (Red Tank, C. Z.) (10) A bee allied to Anthidium taken on the foliage of a Cordia (Ancon, C. Z.). (11) The only Hymenopteron taken at the Cordia flowers was a stingless bee, Melipona orbignyi var. jenningsi Ckll (T. D. A. Cockerell det.) Colcoptera. The series of beetles found associated with the Cordia comprises a considerable number of species. The following taken dur- ing 1923 at Ancon were kindly identified by Mr. H. S. Barber: (1) Ladoria desarmata Muls. (Coccinellid) on foliage. (2) Spermophagus lineolatus Mots (?) (Bruchid) on foliage. (3) Paratenetus tropicalis Mots. (Tenebrionid) bred from dried blossoms. (4) Melanophthalma cartralis Shp. (Lathridiid) bred from dried blossoms. (5) Aidodice nympha Bates (Cerambycid, Fisher det.) Taken by Mr. Zetek on foliage. (6) Psalidonota leprosa Boh. (Chrysomelid) on foliage. (7) Eustylus sexguttatus Champ. (Curculionid, E. A. Schwarz det.) on foliage. (8) Deretomus palmarum Sharp (Curculionid) on flowers. According to Mr. Barber this beetle occurs also in great numbers on the flowers of palms. During the summer of 1924 I captured on the foliage and branches of young Cordias at Ancon 30 additional species, which are still un- identified. These comprise 2 Cerambycids, 1 Telephorid, 2 Lampyrids, wheeler: neotropical ant-plants and their ants 35 1 Lathridiid, 1 Cucujid, 1 Endomychiid, 12 Chrysomelids, 6 Curcu- lionids, 1 Anthibid and 3 Platypodids (boring in a recently felled tree). To this list must be added a second species of Coccidotrophus, C. cordioe Barber (1928), an interesting social Silvanid beetle discovered by Dr. Mann in a single domatium of a Cordia (probably alliodora) at Huachi, on the Rio Beni, Bolivia. This beetle is somewhat larger than C. socialis Barb. & Schwarz, which I found nesting in the petioles of Tachigalia paniculata in British Guiana, but evidently has very similar habits, since Dr. Mann noticed that it was living with its larvae and with Coccids (Pseudococcus sp.) Many of the beetles taken at Ancon were probably chance visitors, but one of them, the Cassidine Psalidonota leprosa, passes through its entire development on C. alliodora, which is therefore to be regarded as its host plant. The beetle was originally described from Mexico (Boheman, 1855). According to Champion (1885-94), it is a common insect in Central America "ranging from the Mexican State of Durango right down to Panama, and probably extending into the northern parts of South America." He cites it from several Panamanian localities. Its range therefore coincides with that of C. alliodora except that it occurs, according to Leng (1920), also in Texas, where it must have a different host plant. The greenish eggs were found in late July and early August in clusters on the lower surfaces of the leaves of young Cordias at Ancon and Red Tank, and the larva? were seen feeding on the same leaf-surfaces in clusters or when older more sporadically. The larva is flattish, pale green, with a blackish-brown mid-dorsal stripe that grows broader with age, especially in the thoracic region, and a fringe of blunt, branched spines along the sides of the body. The posterior end is enlarged into a peduncled sphere beset with knobs and with the protrusible anus at the base of the peduncle on the ventral side. As in other Cassidine larvae, the modified caudal end can be turned forward over the back and supports a great glutinous black mass of faeces and exuviae, which is not, however, large enough to con- ceal the insect. The pupa is naked and attached to the underside of the leaf by its posterior end. The tortoise-like adult beetle, which is nearly a centimeter long and broad, was described by Boheman as "flavotestaceus",and Champion figures it of this color, which suggested the unpleasant specific name leprosa. This is not inappropriate for the dried specimen but is unfortunate, because the living insect is a mag- nificent creature, resembling nothing so much as a large drop of liquid gold. It is therefore a very conspicuous object when sunning itself on the deep green leaves of the Cordia. Since I have found it on the plant 36 bulletin: museum of comparative zoology also early in the dry season, it must have several broods during the year. Orthoptera. The following species of this order were identified by Mr. Morgan Hebard: (1 and 2) Stagmomantis (Mantid), two species, immature, on young foliage of C. altiodora. (3) Cryptostilum antillarum Redt. (Gryllid), living in an abandoned domatium. (4) Gryllacris sp. (Gryllid), immature near picta Bruner, on foliage. (5) Osmilia flavoUmbata De Geer (Aeridiid). At Ancon both Mr. Zetek and I repeatedly took both sexes of this grasshopper in the act of devouring the foliage of C. alliodora. (6) Coscineuta coxalis Serv. (Aeridiid). A few specimens on the foliage of young plants. (7) Schistocerea sp. (Aeridiid), immature. (8) Aidemona azleca (Saussure) (Aeridiid) One female and one im- mature individual. (9) Orphulclla concinnula (Walker). (Aeridiid) One female. (10) Neoconocephalus sp. (Tettigoniid), immature. (11) Anaulacomera sp. (Tettigoniid), immature. (12) Phaneroptera pawnee (Griffini) (Tettigoniid) immature. (13) Phlugis sp. (Tettigoniid), immature. Thysanoptera. Two species of this order have been identified by Dr. J. Douglas Hood: Diccratothrips armatus Bagnall and Elaphro- thrips sp. Both are large slender species, black in the adult and bright coral red in the younger stages, occurring in numbers in some of the dead and abandoned domatia at Ancon and on Barro Colorado Island. A third, unidentified species is a minute yellowish form, common on foliage and flowers at Ancon. Neuroptera. Two species are represented in the collection, one a species of Chrysopa of which Mr. Zetek on several occasions found the eggs attached to the leaves of young Cordias, the other a species of Hemerobiid, the larvae of which I have taken on several occasions in the same situations. Both insects probably prey on the Aphids and Aleurodids. Heteroptera. The following species of this order have been kindly identified by Dr. J. G. Myers and Dr. R. F. Hussey. (1) Proxys punctulatns Pal. Beauv. (Pentatomid) Ancon (Myers det.) (2) Edessa collaris Dall. (Pentatomid) (Myers det.) Ancon. This bug is common in all stages on the plant (except the eggs, which were wheeler: neotropical ant-plants and their ants 37 not seen). The nymphs and adults are green in life. Undoubtedly C. alliodora is a normal host plant of this insect. (3) Hypselonotus fulvus DeG. var. venosus Fabr. (Coreid) Ancon. Range: Colombia, Venezuela, Surinam (Hussey det.) (4) Hyalijmenus pulcher Stal (Coreid) Las Sabanas, Panama. (Myers det.) (5) Dysdercus ruficollis L. (Pyrrhocorid) Ancon (Myers det.) (6) Dysdercus obliqum H S. (?) (Pyrrhocorid) Ancon. Range: Cali- fornia to Ecuador. (Hussey det.) (7) Monanthia monotropidia Stal. (Tingitid) Ancon and Red Tank. (Myers det.) This insect feeds in great numbers and in all stages on the under surfaces of the leaves of C. alliodora and damages them severely, causing them to turn black. It seems to have a wide distribu- tion. Wolcott (1923) found the "nymphs and adults abundant on the underside of leaves of a small unidentified tree in the mountains north of Yanco", Porto Rico. (8) Macrocephalus notatus Westw. (Phymatid) Ancon (Myers det.) (9) Zelus nugax Stal. (Reduviid) Ancon (Myers det.) (10) Eccritotarsus splendens Distant. (Mirid). Ancon (Myers det.) Homoptera. The following species have been identified by Dr. Myers and Dr. W. D. Funkhauser: (1) Monecphora lepidior Fowler (Cercopid) Ancon, feeding on young shoots (Myers det.) (2) Micrutalis balteata Fairm. (Membracid) Ancon, feeding on young shoots. (Funkhauser det.) (3) Micrutalis dubia Fowl. (?) (Membracid) Ancon, feeding on young shoots, (Myers det.) (4) Ceresa bubahis (Fabr.) (Membracid) Ancon (Myers det.) (5) Vanduzca triguttata Burm. (Membracid) Ancon (Funkhauser det.) (6) Brachybelus cruralis Stal (Membracid) Ancon (Myers det.) (7) Oncometopia undata (Fabr.) (Cicadellid) Ancon. Evidently feeds on Cordia. (8) Cicadella sexguttata (Fabr.) (Cicadellid) Ancon (Myers det.) (9) Cicadella rufimargo (Walk.) (?) (Cicadellid) Ancon (Myers det.) (10) Gypona obscurior (Fowler) (Gyponid) Ancon (Myers det.) (11) Gypona postica Walk. (Gyponid) Ancon (Myers det.) (12) Athysanus bicolor Van Duzee. (Jassid) Gamboa (Myers det.) (13) Deltocephalus sp. (Jassid) Ancon (Myers det.) (14) Protalebra sp. (Typhlocybid) Ancon (Myers det.) (15) Rudia diluta Stal. (Tropiduchid) Ancon (Myers det.) 38 bulletin: museum of comparative zoology (16) Cyrpoptus snavis Stal. (Fulgorid) Ancon (Myers det.) (17) Colpoptera sinuata Burm. (Issid) Ancon (Myers det.) (18) Ormenis griseoalba Fowler. (Flatid) Gamboa (Myers det.) (19) Psyllid indet. (nymphal exuvise) Ancon (Myers det.) (20) Aphis sp. (A. C. Baker det.) This species was taken in great numbers on Cordia in November 192.3 by Mr. Zetek. The insects caused the leaves to crinkle and were attended by the common crazy ant, Paratrechina longicornis Latr. (21) Aleurodicus dugcsii Ckll. (?) (Aleurodid) Ancon. Also taken late in November 1923 on the leaves of C. alliodora (A. C. Baker det.) Coccidoe. The following species were recognized by Dr. H. Morrison from extensive collections made in 1923 and 1924. (1) Akermes cordioe Morrison. In domatia with Azteca longiceps and Crypiocerus pollens. Red Tank and Ancon. (2) Coccus hesperidum (Linn.) On leaves and twigs, attended by Azteca velox. Ancon. (3) Cryptostigma biorbicidum Morr. In domatia with Pseudomyrma ita and Azteca longiceps. Ancon and Frigoles. (4) Cryptostigma secretum Morrison. In domatia with A. longiceps. Ancon. (5) Cryptostigma reticidolamin® Morrison. In domatia with A. longiceps. Ancon and Frijoles. (6) Cyclolccanium hyperbaterum Morrison. In domatia with Azteca longiceps and Psexidomyrma ita, Red Tank, and Ancon; with Cam- ponotus brettesi, Barro Colorado Island, and Frijoles; with Azteca pittieri, Pueblo Nuevo, Panama; with Crematogaster tumulifera, Red Tank. (7) Pseudocoecus brevipes Ckll. (previously bromelia 1 Bouche). In domatia with Azteca longiceps. Red Tank and Las Cascades. The Coccid occurs also in the cauline cavities of Triplaris and Cecropia. (8) Pseudocoecus maritimus (Ehrh.) In a young domatium of Cordia, without ants. Red Tank. (9) Pseudocoecus probrevipes Morrison. In domatia with Pseudo- myrma ita, Crematogaster sumichrasti and especially Azteca longiceps. Ancon, Red Tank, Quebrada de Oro, Las Cascades, Barro Colorado Is. & Frijoles. (10) Pseudocoecus sp. immature. In domatia with Pseudomyrma gracilis. Red Tank. (11) Saissetia hemisphaerica Tang. Covering the twigs and domatia of young Cordias and injuring them severely. Collected by Mr. Zetek at Ancon June 15/26. wheeler: neotropical ant-plants and their ants 39 (12) Saissetia nigra (Nietn.) On leaves. (13) Saissetia olew (Bern.) On leaves. (14) Aspidiotus perculeanus Doane & Hadden. On leaves. Myriopoda. Two species of Myriopoda were found occupying old and abandoned domatia. These were identified by Dr. R. V. Cham- berlin as Orphoeus brevilabiatus Newp., a Chilopoda, taken at Red Tank, and Orthomorpha gracilis Koch taken at Ancon. Arachnida. The following spiders, kindly identified by Mr. Nathan Banks, were taken on the foliage of young Cordias at Ancon and on Barro Colorado Island. Many of them were living in webs spun between the leaves or twigs: (1) Gasteracantha kochi Butler. (2) Frontinella uncata Cb. (3) Chrysso vexabilis Keys. This small red and black spider is unusually common on the plant. (4) Runcinia magna Keys. (?) (5) Selenops mexieann-s Keys. (6) Nephila clavipes L. (7) Zygoballus tibialis Cambr. (8) Dendrophantes momus Cambr. (9) Teudis roseus Cambr. (10) Phyale simplicicava Cambr. (?) (11) Pisaurid gen. incert. very young. (12-14) Phyale, 3 species, immature. (15) Dictyna sp., immature. (16) Philodromns sp., immature. (17) Nov. gen. nov. sp. near Simonella. (18) Mites, belonging to the group commonly called "red spiders" were found by Mr. Zetek during November 1923 on both sides of the main ribs and riblets of the leaves of young Cordias at Ancon. "They leave a patch which is almost white, — typical of red spider injury. They were very abundant and lived on the same leaves with the Aphids." Isopoda. A few small white Isopods related to Oniscus were found at Ancon inhabiting an abandoned domatium. Nematodes. Several peculiar species taken in the latrines of the domatia have not yet been described by Dr. Cobb. Fungi and Bacteria. In addition to the moulds which grow on the walls of the domatia there is a powdery mildew of the family Erysiphacese which often covers the leaves of young Cordias. Speci- mens collected by Mr. Zetek at Ancon could not be further identified 40 bulletin: museum of comparative zoology by Prof. W. H. Weston, to whom I sent them, because the fruiting bodies were absent. The bacteriology of the domatial latrines still remains to be investigated. Algoe and Lichens. Like other tropical trees, C. alliodora supports a flora of lichens and algre on its bark. If we consider only the Arthropoda noticed in the preceding pages as visiting or infesting Cordia alliodora we have the following numbers of forms in each of the larger groups : Hymenoptera (including Formicidae) 69 Lepidoptera 6 Diptera 14 Coleoptera 39 Orthoptera 13 Thysanoptera 3 Neuroptera 2 Heteroptera 10 Homoptera (including Coccidse) 35 Myriopoda 2 Arachnida 18 Isopoda 1 Total 212 In all probability this total of more than 200 forms or species represents only a fragment of the bioccenose centering about C. alliodora, because my observations were confined to a very small portion of its known geographical range. The data are nevertheless sufficiently numerous and striking to admit of certain conclusions, especially as they are supported by similar observations on other ant-plants (Tachigalis, Cecropia, Acacia, etc.) to be considered in the sequel. There can be no doubt that C. alliodora has many insect enemies, which destroy or deform its foliage, injure its terminal shoots and withdraw a considerable amount of sap from its tissues. The most numerous and serious of these pests are the moth Conchylodes salamisalis, the Cassidine beetle, Psalidonota leprosa, the Pentatomid bug Edessa collaris, the Tingitid Monanthia monotropidia, a red spider, the various Membracids, Cicadellids and Jassids, the Aphis, the Aleurodid Aleurodicus dugesii and last but not least, the fourteen species of Coccidse recognized by Morrison. No evidence was found to indicate that any of the 54 forms of Formicidse attacked any of the leaf-eating species, though it was evident that they solicitiously wheeler: neotropical ant-plants and their ants 41 attended many of the Coccids to the injury of the plant. Moreover, the majority of the 212 Arthropods, excluding the Formicidse, were found on young Cordias, the domatia of which were as yet either uninhabited or occupied only by recently fecundated, colony-founding queens of Azteca longiccps and pittieri. Hence the plants can derive no protection from these insects in the very stages when the incidence of natural selection should be most effective. Yet none of the thous- ands of young and seedling Cordias which I examined in Panama showed the slightest signs of being killed by its insect pests. I have no hesitancy in asserting that the plant is quite as vigorous and quite as able to withstand the attacks of insects as any other common tropical tree. Chapter 2 OBSERVATIONS ON TRIPLARIS The dioecious Polygonaceous trees of the genus Triplaris and their ants made a more vivid impression than the Cordias on the early naturalists who visited the American tropics. That the natives and colonists had long been duly impressed is indicated by the many ver- nacular names they invented for the plants and their aggressive tenants. As long ago as 1849 Weddell recognized 14 species of Triplaris and in 1S56 Meisner enumerated some 25; Hemslev in 1882-86 and Dammer in 1893, however, recognized only about 10. Probably the latter number is not far from the present estimate of actually existing species, but it must be admitted that there is as much confusion in the botanical literature in regard to Triplaris as to many other genera of Neotropical woody plants. The Triplarises certainly appear to be more local than the Cordias of the Gerascanthus group and are confined to the warmest portions of South and Central America, where they grow by preference in low or even swampy places along streams. One species ( T. auriculata) occurs as far north as Mexico. The genus is not represented in the West Indies, though it may occur on several of the islands adjacent to Northern South America, e.g., Trinidad. Boldingh (1914) cites T. coriacea Karst. as growing in several localities on Curacao, off the coast of Venezuela. (A.) Historical One of the earliest accounts of Triplaris and its ants is that of P. Bernabe Cobo (1653), who in his "History of the New World" says that the tree is called "palo santo" and describes it as follows: "This 42 bulletin: museum of comparative zoology tree is hollow throughout from the trunk to the slenderest twigs and full of certain yellow and largish ants, so virulent that their sting is apt to bring on fever and is always exceedingly painful. Since these ants are concealed within the tree, they are not seen and this is the reason why those who do not know the secret, are not on their guard ; but if a single leaf be touched, so many of the ants swarm forth from all parts of the tree as to excite wonder, and they assail the person who touches the tree and, if he does not withdraw in time, martyr him with their stings." The editor adds the scientific name of the ant as Myr- mica triplarina and its vernacular name as "hormiga tangarana"; the copyist cites the name of the tree as "Guyacum sanctum, according to Raimondi." In the botanical literature Aublet (1775) seems to have been the first to notice the peculiar behavior of the ants and their relation to the tree. Writing of T. americana, which he described and figured (p. 910, PI. 347), he says that the natives of French Guiana call it the "sapa- hakaapolli", and adds: "The ants swarm abundantly throughout the interior of the trunk, the branches and twigs of this tree, in such a manner that when one fells it, one is at once completely covered and cruelly tormented by them, a misfortune which befell me. The only way to get rid of them is to throw oneself into the water." In the famous work on Brazil by von Spix and von Martius (1831), I find the following note on the species of Tococa and Triplaris ameri- cana: "A number of plants, especially those of the genus Tococa, seem to have been designed by Nature herself as domiciles for ants. These bushes bear at the upper end of the leaf-petioles a bladder-like enlarge- ment, in which numerous communities of small red ants nest, and the hollow branches of Triplaris americana L., a slender littoral tree, are often inhabited by innumerable colonies of similar creatures. Woe to him who chances to break off such a branch; a scrambling mass of viciously biting enemies pours down upon him and leaves many blisters on his skin." Robert Schomburgk (1838) observed the same species of Triplaris in British Guiana. He says that it is called the "jacuna" by the Ara- wak Indians, the ant being the "jacuna sae", but that the Warrows call the tree the "epouchari", the Caribis the "itassi" and the colonists the "long John". I find that this name is still applied to both T. ameri- cana and T. surinamensis by the settlers in British Guiana. The fol- lowing is Robert Schomburgk's general description of the former species: "The sandy banks of the inland rivers of Guiana are peopled with them ; and when shrubs, stunted in growth by the poverty of the wheeler: neotropical ant-plants and their ants 43 soil, scarcely reach the height of five or six feet, the Triplaris overtops them forty or fifty feet. The trunk is slender and grows up straight, and its erect branches form a pyramid. As already observed, it is uni- sexual, and the flowers of both sexes are insignificant: those of the male last only for a few days, when they dry up; this is likewise the case with the petals of the female; the segments of the calyx however con- tinue to grow, changing in their growth from green to white and Ver- million, and become so attenuated that the branched nerves are easily perceptible. In that state they are three times as large as the fruit, which is still protected by the tube of the calyx, and the whole might in appearance be resembled to a shuttle-cock. The risps are dense, and the tree presents now a most elegant appearance. One unacquainted with the contrary, would consider the tree covered with white blos- soms, tinged with red, among which the dark green leaves have only occasionally room to make themselves visible. The uncautious botan- ist, who, allured by the deceptive appearance, should approach the tree to pluck the blossoms, would bitterly rue his attempt. The trunk and branches of the tree are hollow, like those of the trumpet-tree (Cecropio), and provided between space and space with partitions, which answer to the position of the leaves on the outside. "These hollows are inhabited by a light brownish ant, about two to three-tenths of an inch long, which inflicts the most painful bites. Its antenna? are placed near the middle of the anterior portion of the head; mandibles triangular; peduncle of the abdomen with two rings; the anus hairy and provided with a sting or piercer {Myrmica Latr. nova species). They fall upon their prey with the greatest virulence, and insert their mandibles almost instantly, as soon as they come in contact with any soft substance, emitting a whitish fluid; their bite causes swelling and itching for several days. If they find them- selves captured, they attack and kill one another like the scorpions." The ant to which Schomburgk refers is undoubtedly a species of Pseudomyrma but he makes the common mistake of confusing biting and stinging; the Pseudomyrmas do both, but the pain is, of course, due to the sting. Richard Schomburgk (1848) gives an even more vivid account of T. americana, which he encountered on the Barama River in British Guiana and, according to his estimate, may grow to a height of 60 to 80 feet. "The peculiar internal structure of the trunk and branches make it one of the most formidable of trees. The internodes are perfectly hollow and separated from one another by horizontal par- titions, so that in this respect the tree resembles Cecropia peltata." 44 bulletin: museum of comparative zoology He correctly describes the yellowish brown Pseudomyrmas and their stinging habits but erroneously refers them to the genus Cryptocerus. "Being unacquainted with the structure of the tree and its formidable inhabitants, and ignoring the warning gesticulations of my Waraus, I was trying to break off one of its boughs, when thousands of these insects rushed out of the small round openings in the internodes, completely covered me and in the greatest fury seized my skin with their jaws and, vomiting a white liquid, buried their terrible stings in my muscles. But not only had the ants from the severed portion of the bough fallen into our corial, but thousands more poured out of the openings in the stump and rained down into the boat since the whole colony had been aroused by the shaking of the tree. A few powerful strokes of the oars carried the boat out of the neighborhood of the tree and in the twinkling of an eye the whole crew was in the water, for only thus could we escape from the savage onslaughts of the ants. Even a few tame apes and parrots were not spared. The former with wild leaps freed themselves from their tethers and jumped into the river after us, although few animals are more averse to water. The sting of this yellow-brown ant is only less painful than that of Ponera clarata. The swelling, inflammation and pain may persist for several days . . . After we had cleaned the ants out of the boat with considerable labor and many excruciating stings, we continued our voyage. I must confess that thereafter a secret horror crept over me whenever we passed one of the trees." In 1849 YVeddell described eight species of Triplaris from various parts of South America and published a key for the identification of the known forms. The following account, concealed in a footnote recently detected by Dr. J. Bequaert (1921-22), shows that Weddell was well-acquainted with the trees and their tenants: "The trunk, the branches and even the small twigs of the species of this genus are fistulose and serve as habitations for a peculiar species of ant which exhales when excited a rather agreeable odor like that of the Cicin- delids. If one happens to touch the trunk of a Triplaris, and especially if one imparts a shock to it, the ants sally forth by the hundreds from the interior of the tree through the small galleries which connect the medulary canal with the outside; and if one move not away very quickly, one is covered with these dangerous hosts, whose bite is more painful than the sting of any other insect with which I am acquainted. It is a singular fact that at no matter what period of their life the Triplaris be examined in their forest, these ants are always sure to be encountered. It is singular also that in Rupprechtia, wheeler: neotropical ant-plants and their ants 45 which some authors unite with Triplaris, they are never found. I do not believe that this insect has been observed under conditions other than those I have noted. Its linear form is peculiarly adapted to its mode of life. I have had occasion to examine it and even to suffer from its attacks in many parts of Brazil, Bolivia and Peru, and every- where it seemed to me to be identical. Several travellers have already made known a portion of the facts here related and have placed the Triplaris ant in the genus Myrmica of Latreille, but I am not aware that it has been given a specific name. That of Myrmica triplarina might be applied to it. It is usually pale brown. Its length is 6 to 7 millimeters, its width one millimeter; the abdomen is cylindrical and somewhat attenuated at the posterior end which is hairy." I believe that the ant here described is the same as the one now called Pseudo- myrma arborissanctoe Emery, but this species has a number of local races and varieties and the brief description renders it impossible, unless Weddell's types should be discovered in some European museum to determine which of the described subspecies or varieties should bear the name triplarina. It seems best therefore to regard it merely as a somewhat doubtful synonym of some one of the forms, preferably of the typical arborissanctoe. Spruce (1869, in 1908) mentions several lignescent genera of Neotropical Polygonaceae as harboring ants in their medullar cavities — Triplaris, Coccoloba, Campderia, Symmeria and Rupprechtia — the last in contradiction to Weddell's statement quoted above. 1 "Not only is every lignescent Polygonia a habitation for ants, but the whole of the medulla of every plant, from the root nearly to the growing apex of the ramuli, is scooped out by those insects. The ants make a lodgment in the young stem of the tree or shrub, and as it increases in size and puts forth branch after branch, they extend their hollow ways through all its ramifications. They appear to belong all to a single genus, and are long and slender, with a fusiform, very fine-pointed, dark-coloured, shining abdomen, and they all sting virulently. They are known in Brazil by the name of "Tachi" or "Tacyba", and in Peru by that of "Tangarana"; and in both countries the same name is commonly applied to any tree they infest as to the ants themselves." Spruce describes three species of Triplaris. "Triplaris surinamensis Camb., a Polygonaceous tree of very rapid growth, reaching at maturity a hundred or more feet in height, and conspicuous from afar when in fruit from the abundance and bright 'Apparently the onlv species of Rupprechtia which harbors ants in its internodes is Jamesoni Meisner. (Bequaert 1921-22) 46 bulletin: museum of comparative zoology red colour of its enlarged shuttle-cock-like calyces, is common all along the Amazon, both on the river banks and in marshy inland sites; and solitary trees of it are often seen standing out above the Cacao plantations. T. Schomburgkiana Benth., a smaller tree, grows in the same way in the Upper Orinoco and Casiquiari. These trees as well as the other arborescent Polygonepe, have slender elongated tubular branches, often geniculate at the leaf-nodes, and nearly always with perforations, like pinholes, just within the stipule of each leaf, which are the sallyports of the garrison, whose sentinels are besides always pacing up and down the main trunk, as the incautious traveller finds to his cost when, invited by the smoothness of the bark, he ventures to lean his back against a Tachi tree." The third species of Triplaris allied to surinamensis, was observed in the cinchona forests of Chimborazo (2000-5000 ft.) and at lower levels. Spruce says that it is called by the Guyaquilians the "arbol de frios" (malaria tree), and that its presence "is a pretty sure indication of a humid site." Huth (1887) states that H. von Ihering called his attention to the following account of the Brazilian Triplaris nolitangere Wedd. by J. Severiano da Fonseca (1881): "The Pao de novato is the Taixy of Para and is also called Pau formiguero, or ant-tree. It is remarkable because it harbors in its cavities a kind of ant which is called 'novato'. These ants are yellow, as large as a 'suava' and bite painfully. They live there by the million and drive the inexperienced traveller to des- peration when he attempts to fell and make use of the tall, straight trunks of the 'novato.' " Schimper (1888) had no opportunity to study Triplaris in the field but examined several branches of T. caracasana Cham, and Schl. from the "tierra caliente" of Venezuela, a tree which is called the "palo Maria" by the natives. 1 He says: "The numerous pieces of branches sent to me show nothing that can be interpreted as an adaptation to the ants. Within the branches there is a cavity about 5 to 8 mm. broad, interrupted by diaphragms and connected, with the outside by round openings which are made by the ants. Of the latter there is almost without exception only one at each internode and usually at the upper end of a groove which runs to the next leaf below. The wall of the hollow cylinder is somewhat thinner at the groove, which is caused by the pressure of the bud and occurs also in many other plants. This thin area evidently determines the point 'In some parts of South America (Bolivia) Triplaris is called the "palo santo". This and the name "palo Maria" are obviously of rather recent Christian origin. It has been claimed by- some writers that the "santo" refers to Christ's blood, as symbolized by the massed crimson fruit of the tree. wheeler: neotropical ant-plants and their ants 47 of perforation, which in the great majority of cases is at the upper end of the groove and may be due to the ants selecting, when making their orifices, only those lenticels that are situated in the upper end of the internode." Meinert (1892) published a brief note on a species of Triplaris (probably caracasana) and its ant, which he observed at La Moca, Venezuela. The ant was referred to the genus Myrmica but was obviously a Pseudomyrma. His statement that it is not confined to the Triplaris but occurs abundantly on other plants, has little weight, because there are many Pseudomyrmas which an observer unfamiliar with the species, might mistake for the true Triplaris inhabitant in the field. Warming (1894), who was with Meinert in Venezuela, investigated a Triplaris (presumably caracasana) at Las Trincheras, concentrating his attention on the structure of the elliptical cleft near the upper end of each internode. This structure, as we have seen, was interpreted by Schimper as due to pressure exerted by the bud at the node below or as arising from a lenticel. Warming adopted the former inter- pretation but studied the internodes more closely. Like Schimper he found the wall of the internode to be thinner and to have more feebly developed fibrovascular bundles in the region of the cleft elliptical area and believed that this attenuation induces the ants to select the spot for perforation. But he noticed considerable irregularity in the perforations and their absence in some or all the internodes of whole twigs. He seems to have been the first to notice the numerous white Coccids which the ants keep in the cavities. The ants are briefly described in Warming's paper as "en lille, brun umaadeleg bidsk Art" (a little brown, intemperate, biting species) and referred to Pseudomyrma mordax Meinert. This, however, seems to be a nomen nudum. Forel (1905), who listed the ants collected by Meinert in Venezuela referred the specimens from Triplaris to Ps. arboris- sanctoe subsp. symbiotica Forel, a race originally described from Colombia. Morteo (1904) studied preserved material of Triplaris americana which had been grown under cultivation in the East Indies, where its cavities were inhabited by a common Oriental ant, Dolichoderus (Hy- poclinea) bituberculatus Mayr. He devoted particular attention to the peculiar cleft area near the tip of each internode, but interpreted the fissure as caused by expansion of the pith. He also believed that the ants perforate the cleft in order to feed on the pith, which he found to contain sugar. Like Warming, he found numerous Coccids in the in- 48 bulletin: museum of comparative zoology ternodal cavities. The discovery of sugar in the pith led him to regard it as a substitute for the extrafloral nectaries of other myrmecophilous plants. His observations, if correct, might be suggestive in connection with the presence of Coccids on the walls lined with the remains of the pith, but his statements in regard to the ants devouring it are not to be taken seriously, in view of the fact that his investigations were based on herbarium material. Forel (1904) gives the following account of a species of Triplaris (probably americana) and its ant (Ps. arboris-sanctce subsp. symbiotica) which he encountered in 1896 in the Sierra Nevada de Santa Marta, Colombia: "Having laid my hand on the trunk of a young, green tree about four meters high, I was stung and found that the aforementioned Pseudomyrma was present on the trunk and had caused the sting. Observing the aggressive behavior of these ants, I suspected that they bore a symbiotic relation to the tree, because other Pseudomyrmas, which run about on the trees, flee instead of attacking. But seeing no dry branch and no opening, I was puzzled at first. I accosted some passing Indians and induced them to fell the tree with their machetes. I then broke up its flexible and living branches and found that they had a very narrow medullary cavity. This cavity, extending from end to end of all the branches, constituted the nest which the Pseudomyr- mas occupied in a file, one behind the other, with their males, larvae and pupse, so that they were just able to pass one another, notwith- standing the slenderness of their bodies. This singular habitation baffled me considerably and I asked myself how the colony-founding queen could have penetrated into this perfectly green tree, without a dead branch and apparently without an orifice. After long and vain scrutiny of all the branches, I inspected the lower portion of the trunk and there at last detected the dried and broken remains of an early twig, about 3 mm. in diameter but provided with a medullary cavity communicating with the central cavity of the trunk itself. This it was that served as an entrance and exit for the Pseudomyrmas." It would seem that Forel must have overlooked the small openings which were in all probability present in the tree he examined, as in all other species of Triplaris, near the ends of the internodes of the branches and twigs. The same author, after his description of Pseudomyrma dendroica, states that Prof. E. Goeldi first found this ant in the medullary cavities of young Triplaris trees three to four meters high, and that "having transported the Triplaris inhabited by this ant from the Rio Purus to the botanical garden at Para, he observed that the Pseudomyrma soon took possession of one of the Triplaris in the garden, which had not wheeler: neotropical ant-plants and their ants 49 been inhabited before. The habits of this ant are therefore the same as those of arbor ■issanctoe." Ule (1907) describes Triplaris Schomburgkiana and surinamensis and gives some excellent figures of the former. The natives of the Amazon, he says, call these trees "arvore de tachi" or "tachiceiro", and distinguish the two species as white and black, Schomburgkiana having a pale and surinamensis a dark trunk. "The two species of Triplaris accordingly harbor in their interior a pale and a dark ant." Schomburgkiana is inhabited by Pseudomyrma dcndroica var. emarginata Forel, which nests by preference in the twigs and the crown of the tree but retains a medullary gallery through the trunk, reaching to the ground and sending off lateral galleries at intervals. "The bite of this ant is very painful, burns as if one had come in contact with red-hot iron and sometimes produces blisters on the affected parts of the body. From the trunk the ants wander to the ground and there destroy all the growing vegetation within a radius of a few meters. The location of Triplaris trees can be detected at once by such bare spots in the forest." T. surinamensis is confined more to the banks of rivers and lakes. The darker ant which inhabits its internodes is Ps. triplaridis Forel. It does not make a cleared area around the trunk of the host tree. According to Ule, "the Triplaris trees are of some importance in the landscape. When they are in bloom, the male flowers first be- come conspicuous because they resemble great feather dusters, then the panicles of the female trees stand forth, when the fruits have de- veloped their bright red wings, being vivid purple in Triplaris Schom- burgkiana Benth. and rose-red in Triplaris surinamensis, so that the in- habitants believe that the trees are in flower. When I sailed up the Upper Amazon to Iquitos in July, the shores were everywhere brilliant with the Triplaris trees which with their rose-red fruits and the fresh green of the vegetation after the floods, produced an impression of spring." Pittier (1908) has published a brief note on Triplaris tomentosa Wed., which he observed in Costa Rica, where it is generally called the "hormigo." It is "a small tree of the tierra caliente of the Pacific slope. It is dioecious, with the inflorescences more or less red and showy; the wood, which is of no use, is hollow and always infested with ants. In Nicoyo this tree is called "tabaco". According to Pittier, the Brunka Indians call it the "turi-svan-kra." In 1913 I published some notes on Triplaris americana (under the name Cumingiana Fischer and Meyer) and auriculata Meisn. (Macom- bii Don. Smith). The former I observed in Panama, the latter in 50 bulletin: museum of comparative zoology Guatemala. My visits to Panama in 1923 and 1924 yielded much additional information in regard to americana and I have recently identified the ants taken in the internodes of auriculata. It will be advisable, therefore, to give a revised account of these plants and their tenants in the sequel. Ule's statement that the ants inhabiting T. Sehomburgkiana make a clearing around the base of the tree, is of interest in connection with a communication made to me by Mr. C. D. Mell. According to this student of tropical forestry, T. americana is very abundant in Vene- zuela, where the inhabitants call it "barabas" and where he has seen many specimens, each surrounded by a cleared area, "perhaps made by the ants." It is well known that two of our North American species of Pogonomyrmex, barbatus and occidentalis, make clearings around their nests by destroying the vegetation and that our common Formica exsectoidcs sometimes behaves similarly in our northern woodlands. There is, therefore, no reason to suppose that Pseudomyrma dendroica may not have developed a similar habit, though nothing of the kind has been observed in other species of the genus. (B) Triplaris surinamensis Cham. & Schl. The only species of Triplaris which Professor I. W. Bailey and I had an opportunity to examine in British Guiana was surinamensis, the "long John" of the colonists. It seems to be very common in Dutch Guiana, where, according to Pulle (1906), it is known to the settlers as the "mira-hoe-hoe", or "mierenhout" (ant-tree). We were unable to find it in the immediate vicinity of the tropical laboratory at Kartabo, but on August 4, 1920, a native guided us to a spot near Camaria, some seven miles up the Cuyuni River, where there was a small grove of young and vigorous "long Johns", about 20 to 30 feet high, growing on the low bank. The river, owing to the daily rains, was so high that the roots and bases of the trunks were under water and the dense un- dergrowth around them impeded our approach. We succeeded, never- theless, in securing a number of boughs and placed them in the canoe — a very painful task, because all the foliage was swarming with a single very vicious species of Pseudomyrma. The native evinced great fear of the insects, insisting that they cause fever. 1 While the canoe was being towed the ants swarmed along the painter into our launch and tortured us all the way down the river to the laboratory. ■The natives make the same statement in regard to the powerful Ponerine ant, Paraponera claiata Fabr. and in Southern Brazil and Bolivia concerning the even larger Dinoponera grandis Guer. wheeler: neotropical ant-plants and their ants 51 The twigs and branches of surinamensis exhibit the same peculiari- ties as those of other species as described by Schimper, Warming, Spruce and Morteo. Professor Bailey, who studied the morphology of the internodes and of the peculiar oval, slit-shaped, area at their upper ends in the material we collected, has contributed the following paragraphs and several photomicrographs of sections to illustrate his interpretation : "The fistulose stems of Triplaris surinamensis are characterized, as are other representatives of the genus, by the presence of a slit-like opening in the distal portion of each internode. Are these openings, which serve as convenient entrances and exits, spontaneous structures or are they excavated by the ants? An examination of immature shoots reveals the fact that the slit-like orifices originate during the earlier stages of the enlargement of the internodes, and that they are due, in all probability, to asymmetrical growth and differentiation of the cortical, fibrovascular and medullary tissues. As in the myrme- cophytic Cecropias, one longitudinal surface of each internode is flattened or slightly concave and is subtended by a leaf and its ac- companying axillary bud. The growth and differentiation of the tissues is retarded in this side of the internode which is, in consequence, some- what thinner and considerably weaker (Plate 10, Fig. c). This tendency toward asymmetrical development is accentuated at the distal end of the internode, below the insertion of the lateral organs of the next (higher) node, and the concomitant peripheral tension ruptures the delicate tissue in the thinner portion of the circumference of the cauline cylinder (Plate 10, Fig. a). The asymmetry is emphasized in vigorous, rapidly differentiating shoots and a sub-nodal aperture is formed in each internode. On the contrary, in stunted, slower-growing twigs, which are more nearly cylindrical, the distribution of the slit- like openings is rather sporadic. The apertures tend to become oc- cluded by a growth of callus from the margins of the ruptured tissues (Plate 10, Fig. b) before the enlarging internodal cavities are taken possession of by the ants. Indeed, many of them are not subsequently reopened. Those that are, are characterized by having small circular apertures gnawed through the occluding callus. "Coccids more or less numerous are found associated with the ants in the internodal cavities of T. surinamensis. In Cecropia, Tachigalia, Cuviera, Plectronia and various other Neotropical and Ethiopian ant- plants, the guest ants excavate pits in the denser tissues of the cauline cylinder which enable the Coccids to feed upon the softer tissues or upon a traumatically induced, thin-walled, centripetal callus. In T. 52 bulletin: museum of comparative zoology surinamensis the internodal chambers are jacketed by a thick, peri- pheral layer of medullary tissue (Plate 10, Fig. d), which remains green and physiologically active, even in stems which have formed a thick layer of secondary wood. The Coccids are able to insert their setae into and to feed upon this medullary tissue. In other words, there is no evidence to indicate that the ants are concerned in facilitating the feeding of the Coccids. Although there is no reliable evidence at present for assum- ing that the imaginal ants solicit and feed upon the sugary exudates of the Coccids, an analysis of pellets fed to the larvae indicates very clearly that the workers carve up the Coccids and feed them to the brood. (Plate 10, Fig. e.) "The refuse of the ant-colonies, i.e. voided infrabuccal pellets, liquid faeces, fragments of malaxated insects, triturated plant-tissues, etc., is deposited at intervals along the walls of the elongated chambers. These latrines or middens give rise to luxuriant growths of delicate fungus hyphae which are fed upon by an interesting group of structurally highly specialized Nematodes. The writer's investigations of Neo- tropical and Ethiopian myrmecophytes indicate that fungi are not cultivated and eaten by the ants, but that the aerial hyphae are pe- riodically cropped to prevent them from obstructing the chambers and interfering with the brood. That the middens in T. surinamensis may at times be utilized in the feeding of the brood is shown by analyses of the contents of the larval food-pouches, or trophothylaces. Not infrequently the pouches are filled with mats of hyphae (Plate 10, Fig. f) or wads of detritus containing large numbers of Nematodes. It should not be inferred from this, however, that the imaginal ants actually cultivate the fungi, as do the Attini, or that they themselves feed upon hyphae or Nematodes." The fierce, aggressive ant inhabiting the T. surinamensis trees near Camaria, B. G. proves to be a darker and more slender race of Pseu- domyrma triplaridis Forel, which was taken by Ule, Goeldi and Huber in the same species of Triplaris in Brazil. I have described it as subsp. baileyi. The many flat Coccids of all sizes found in the internodal cavities were identified by Dr. Harold Morrison (1922) as a new genus and species, Farinococcus mvltispinosus Morr. and Ahermes secretus Morr. They are sufficiently numerous to suggest that they may furnish the ants with considerable food in the form of honey-dew, especially during the rainy season. But certain observations, both negative and positive, cast doubt on this supposition. In the first place, no one has seen Pseudomyrmas attending Coccids or imbibing their sweet excreta. And when the twigs are broken open and the ants escape, they are wheeler: neotropical ant-plants and their ants 53 never seen to seize the Coccids and carry them away, like the species of Azteca and many other ants when similarly disturbed. These negative observations indicate rather that the Coccids may, while still very young, find their way into the internodes, either through the preformed clefts or through the openings made by the ants, and settle on the walls without being molested and perhaps without being noticed at first by the ants. But that the latter may utilize the Coccids, though not as dairy cattle, is shown by Professor Bailey's observations, which con- firm our statements in regard to other species of Pseudomyrminae (Wheeler and Bailey, 1920; Bailey, 1922, 1923). As he has remarked, examination of the internodal cavities shows that there are in certain situations in the walls, latrines, or middens consisting of pellets ejected from the infrabuccal pockets of the ants and over-grown with luxuriant fungus mycelium inhabited by great numbers of Nematode worms. These latrines are strictly comparable with those of Azteca longiceps in the Cordia aUiodora swellings described on p. 20. But unlike the Azteca, Pscudomyrma bailey i makes good use of the latrine materials, since the workers collect the hyphse, Nematodes, particles of infrabu- cal pellets and pieces of Coccids and fashion them into food-pellets which they place in the trophothylaces of their larva?. Since the Coc- cid fragments thus employed are rather numerous we suspect that the adult ants frequently devour these insects, possibly after they attain the proper dimensions, and horribili dictu serve up merely the remains mixed with other garbage from the latrines as the most appropriate or at least as the most available food for their progeny. The Coccids are used, therefore, as Bailey (1923) says, "for beef rather than solely as immature milch cows." Since there is a continuous growth and multi- plication of Coccids, fungi and Nematodes in the internodal cavities, we are able to understand how the ants can develop and maintain large colonies in a plant which, so far as known, has neither extrafloral nectaries nor food-bodies such as we find in the myrmecophytic Acacias and Cecropias. Whether the ants also eat, instead of merely excavating, the sugary pith in the young internodes, is doubtful, but if Morteo's contention is correct, the plant itself does furnish an addi- tional and perennial food-supply. The foregoing observations afford, I believe, at least a partial solution of the enigma which has puzzled several myrmecologists who have been unable to understand how the Pseudomyrmas not only survive but flourish in trees which normally grow in swampy places or on river banks where for several months each year they are isolated by high water. At the time of our visit to Camaria, the ants in the surinamensis 54 bulletin: museum of comparative zoology trees were at the acme of the breeding season, the internodes of the twigs and branches being stuffed with the slender larva? and pupae in all stages, intermingled with recently emerged males, females and workers- The Coccids, too, were flourishing. Obviously the rainy season, which increases the sap in the tree, is most favorable to the de- velopment of the Pseudomyrma colonies, the Coccids, fungi, and Nematodes, and it may be confidently predicted that the Coccids will show a considerable decrease in numbers during the dry season. But then the ants can move more freely over the surrounding vegeta- tion and secure many small, miscellaneous insects as food. In the gardens of private residences in Georgetown, B. G., Professor Bailey and I noticed a few large surinamensis trees and on their trunks several different ants, but we had no opportunity for further investi- gations. A few years ago Mr. H. E. Box sent me from Blairmont, Berbice, B. G. a considerable amount of material of T. surinamensis containing ants and Coccids. The ants proved to belong to two different sub- species of Pseudomyrma triplaridis, which are described in the sequel (p. 184, 186) as subsp. boxi and tigrina. They resemble baileyi but are reddish. There were two species of Coccids, one being the same as the Farinocoecus multispinosus Morrison, taken at Camaria, the other Cryptostigma quinquepori Newstead. So far as known, therefore, T. surinamensis harbors in various parts of its range eight different organisms, namely, four subspecies of Ps. triplaridis, two Coccids, at least one species of fungus and one Nema- tode. That this can be only a small fragment of the bioccenose which centers about T. surinamensis is evident from the following account of T. americana of which I was able to make a more thorough study. (C) Triplaris americana Linne My first acquaintance with T. americana dates from December 1910 when Mr. E. D. Christophersen showed me near Empire in the Canal Zone a few of the trees growing in a swamp which is now at the bottom of Gatun Lake. 1 At that season they were not in bloom. During my 'I had identified the plant (1913) as T. Cammingiana Fischer and Meyer, which is cited from the Isthmus by Seemann (1852-57) and Hemsley (1882-86). My identification was later confirmed by Professor B. L. Robinson of the Gray Herbarium. Meisner (1S56) obviously redescribed the same species as T. columbiana. I now find that the Panamanian plant should be known as T. americana L., according to Standley (192S p. 171), who describes it as the only Central American species of Triplaris. He states that "in Panama the tree is sometimes known as the "palo santo' (a name given more commonly to Erythrina glauca), but oftener as "guayabo hormiguero", while in Salvador it is called "mulato" and "palo mulato." wheeler: neotropical ant-plants and their ants 55 two more recent visits to Panama in 1923 and 1924 I was able to make a much closer acquaintance with the plant and its inhabitants. It is less abundant than Cordia alliodora and grows singly or in small clus- ters on low lands along the water-courses or on the lower slopes of ravines which carry a considerable amount of water during the rainy season. On my frequent trips across the Isthmus I noticed single specimens or small groups of the tree in many parts of the Zone within a mile of the railway from Frijoles to Balboa. A few scattered speci- mens were seen near the ruins of Old Panama in the Republic, but none was observed in the dryer savannah region somewhat further inland. Numerous accessible trees were found during 1923 in three localities: along the stream below the large, abandoned cacao plantation at Las Cascades, on the low banks of the Rio Grande between Ft. Clayton and the locks at Miraflores, and in the ravines descending from Ancon Hill behind the new administration building at Balboa. Unfortunately clearings were being made in the two localities first mentioned and a number of the trees were being felled, but at Balboa more intelligent and appreciative persons in charge of destroying the rank vegetation had carefully spared the Triplaris trees. In the ravine nearest the ad- ministration building there are a dozen beautiful specimens, which being within a short walk of Mr. Zetek's laboratory, could be visited at frequent intervals. During 1924 I found a few trees also in the swampy land at Marajal, near Colon, on the Atlantic side of the Isthmus. T. americana is a small tree which rarely attains a height of more than 20 to 35 feet, with slender trunk and pyramidal crown, smooth gray bark, reddish twigs and bright green, drooping, smooth, entire, lanceolate leaves, about 5 to 8 inches long, with prominent veins and midrib. The cavities in the trunk, branches and twigs are precisely like those described for other species of the genus and the cleft elliptical areas at the distal ends of the internodes of the twigs show the same peculiarities as in the forms described by Schimper, Warming, Morteo and Bailey. The small round perforations made in the clefts by the ants are also very similar. The trees were found in bloom from February 25 till March 30. The spikes of small, sweet-scented, greenish white male flowers persist for only a short time, but in the female plant they are soon replaced by peculiar, rapidly enlarging, shuttle- cock-shaped, fruits, which are at first green, then whitish and finally pure crimson. When the tree reaches this stage it is a very handsome and conspicuous object which might be advantageously introduced into the gardens of Southern Florida, California and the West Indies. 56 bulletin: museum of comparative zoology The shape of the fruits, with their long wings, indicates that they may be disseminated by the wind, like the samaras of our maples. I was unable to find any seedlings, and the smallest trees observed were not less than five or six feet high. All the specimens of amcricana I have seen had ants nesting in their cavities, but the fauna is much more diverse than I had inferred from my meager observations of 1910, when the only ant encountered near Empire was a yellowish Pseudomyrma which I identified as arboris- sanctce Emery. This ant has since been described by Forel as a distinct variety, loewensohni of the Colombian subspecies symbiotica of Emery's species. During 1923 and 1924 I took the following 16 species in or on the Triplaris in the various localities mentioned above: (1) Pseudomyrma alliodorce Whir. Balboa; Miraflores; in twigs. (2) Pseudomyrma gracilis Fabr. var. bicolor Guerin. Balboa; Mira- flores; in twigs. (3) Pseudomyrma sericea Mayr var. ita Forel. Balboa; in twigs. (4) Pseudomyrma triplarina Weddell subsp. symbiotica Forel var. loewensohni Forel. Balboa; Las Cascades; Frijoles; Marajal; in twigs, trunk and branches. (5) Crematogaster (Orthocrema) limata F. Sm. subsp. parabiotica Forel. Miraflores; in twigs. (6) Crematogaster {Orthocrema) brasiliensis Mayr. var. ludio Forel. Miraflores; in twigs. (7) Crematogaster {Orthocrcma) brevispinosa Mayr. var. ampla Forel. Balboa; Las Cascades; in twigs. (8) Cryptocerus (Paracryptocerus) minutus Fabr. Miraflores; in twigs. (9) Atta cephalotes L. Balboa; cutting leaves and collecting flowers. (10) Dolichoderus {Monads) bispinosa Oliv. Frijoles; visiting flowers. (11) Azteca theresiaz Forel var. menceps Forel. Miraflores, Balboa, Las Cascades; in twigs and branches. (12) Azteca vehx Forel. Las Cascades; attending Coccids on branches. (13) Tapinoma melanocephalum Fabr. Balboa; in twigs. (14) Brachymyrmex heeri Forel var. obscurior Forel Balboa; in twigs. (15) Brachyinyrmex pictus Mayr. subsp. balboa? Whir. Balboa; in twigs. (16) Camponotus {Myrmobrachys) lindigi Forel. Balboa; attending Coccids on branches. Four of these ants, Atta cephalotes, Dolichoderus bispinosus, Azteca velox and Camp>onotus lindigi merely visit the trees. The Camponotus and Azteca attend Coccids on the twigs and stems of the flower- panicles, and the Atta may perhaps cut and collect the fruits. The remaining 12 species were all found nesting in the fistulose twigs and wheeler: neotropical ant-plants and their ants 57 branches, but only two, Pseudomyrma loewensohni and Azteca menceps are obligates, most if not all the others occurring also in other myr- mecophytes or even in the dead twigs of various trees and shrubs. The singular fact was disclosed that Ps. loewensohni was altogether absent from the trees in the Miraflores locality and present only in a certain number of those near Las Cascades, Balboa and Mirajal. Many trees were inhabited in great part or entirely by the Cremato- gasters and A. menceps, the latter being the most common. The other forms in the list were usually confined to single twigs or branches of trees tenanted also by this Azteca or one of the Crematogasters. When Ps. loewensohni was present it usually had complete possession of the tree. These statements may be illustrated by the distribution of the ants recorded in my note book under the date of March 26, 1923 as occupying the 12 trees in the ravine at Balboa behind the administration building. (1) Tree about 15 ft. high; fruiting. Twigs inhabited exclusively by A. menceps. (2) About 30 ft. high, with two trunks; flowering. Twigs inhabited by C. ampla and B. obscurior. (3) About 30 ft. high, beginning to fruit. Twigs occupied by C. ampla. (4) About 9 ft. high, in flower. Twigs and branches inhabited by Ps. loewensohni exclusively. (5) About 15 ft. high; beginning to fruit; leaves much eaten. Twigs tenanted by C. ampla. (6) About 20 ft. high; in flower. Tenanted throughout by Ps. loewensohni. (7) About 20 ft. high; in flower, but with several dead branches. Twigs occupied by A. menceps. (8) About 35 ft. high; beautiful specimen, flower. Tenanted by A. menceps. (9) About 25 ft. high, in flower. Twigs inhabited by A. menceps and B. balboce. (10) About 35 ft. high, in flower. Tenants: A. menceps (abundant); Ps. attiodorce (sporadic); C. lindigi running on trunk and foliage. (11) About 35 ft. high; mature fruit. Tenants: B. balboce (in several branches) ; Ps. bicolor (sporadic) ; C. lindigi running on trunk. (12) About 30 ft. high; just passed flowering. Tenants: C. ampla (abundant) ; T. melanocephalum (in a few internodes) ; Ps. ita (sporadic); C. lindigi running on trunk and branches. 58 bulletin: museum of comparative zoology My notes on these trees are very brief and may not represent an accurate census, especially of the inhabitants of the larger specimens, because, owing to their height, I was unable to make an exhaustive inventory of their twigs and branches. Moreover, the trees were being preserved for ornamental purposes and could not be mutilated. I believe, nevertheless, that few species of ants, and only those forming very small sporadic colonies in some of the internodes, were overlooked. Quite a number of twigs from most of the trees were cut off, carried to the laboratory in bags and chloroformed so that the ant colonies could be carefully examined. It will be seen that only two of the twelve trees were inhabited by Ps. loewensohni, whereas five contained A. menceps and four C. ampla. One of the largest harbored none of these species. In the series of more than 20 trees between Ft. Clayton and Miraflores, those nearest the former locality were inhabited exclusively by A. menceps, those nearest the latter by Crematogaster ludio, with a few sporadic colonies of Cryptocerus minutus. Near Las Cascades only three among a dozen trees examined, were tenanted by Ps. loewensohni, and one of these, a vigorous specimen about 15 ft. high, which was felled and carefully examined, also had A. menceps in some of its twigs. Many of its smaller branches were quite free from ants and in part inhabited by the larvse of a Thyridiid moth (vide infra, p. 60), which was common also in many of the trees in the other localities. Since, apart from the sporadic Ps. ita and bicolor, the only ant listed that stings painfully is Ps. loewensohni, and since it occurred only in a small number of the trees and was even entirely absent in one locality, T. americana, unlike its various South American congeners (Schomburgkiana, caracasana, surinamensis, etc.,) could usually be handled and examined with impunity. And while it is not improbable that in some Panamanian and Colombian localities the plant may be inhabited exclusively by Ps. loewensohni or the typical subsp. symbiotica or by vicious species other than those enumerated in my list, a study of the trees in the Canal Zone shows that specimens harboring only such small inoffensive ants as A. menceps, C. ampla and ludio, are quite as vigorous and flourishing as those inhabited by the red, stinging Pseudomyrma. At Balboa, in fact, this ant did not occur in the largest and finest trees. Besides the case above mentioned of loeicensohni living in the same tree as A. menceps, the following observation shows that the Pseudomyrma is not a very aggessive protector of its tree from alien ants. On March 28 at Frijoles, I came upon a Triplaris about 14 ft. high which had just wheeler: neotropical ant-plants and their ants 59 been felled by a native. It was in full fruit and the large crimson panicles had been invaded for some reason by a host of the belligerent Dolichoderus bispinosus. Closer examination showed that the cavities of the tree were occupied by a thriving colony of loewensohni, the workers of which were running about quietly and without the slightest signs of hostility among the Dolichoderi. The following observation made at Balboa, March 25, indicates, perhaps, that the other ants of T. americana are quite as indifferent to invasions of their host tree by alien species. A few feet from the trunk of tree Xo. 12 at Balboa there was a large nest of Atta ccphalotes, but all the ants had withdrawn into the depths of their galleries. That they had been working during the preceding night was shown by the great masses of Triplaris flowers which they had carefully collected and left in the runways leading to their nest-craters. Of course, these wilted flowers may have been merely picked up on the ground, but that they may have been culled directly from the trees is by no means improbable. I may add, in this connection, that a few of the trees near Fort Clayton, though inhabited by flourishing colonies of A. menceps, nevertheless had their leaves severely damaged by Atta cephalotes. Before listing the miscellaneous organisms associated with T. ameri- cana and with its ants, it will be advisable to insert a few remarks on the two obligates, Azteca menceps and Pseudomyrma loewensohni. The types of the former were taken by Christophersen in the Canal Zone but the precise locality was not recorded. They were probably from the very trees to which he guided me in 1910. The habits of this ant are similar to those of A. longiceps, described above (p. 28), and the fullest development of its colonies occurs at the same season, coinciding with the anthesis and fruiting of the host-plant. Like the other Triplaris ants, menceps makes small round entrances in the elliptical cleft areas of the internodes and also destroys the partitions between them so that their cavities become continuous. The walls of the cavities also have gnawed pits containing Coccids, which are rather numerous, pinkish in color and covered with white wax. There are, moreover, definite latrines at intervals on the walls, like those of A. longiceps in the cauline swellings of Cordia alliodora and consisting of numerous pellets from the infrabuccal pockets of the ants, covered with proliferating fungus hyphee and invaded by hosts of Nematodes and bacteria. Mites are also present occasionally. The pellets them- selves consist of spores and small pieces of insects and plant tissue. Ps. loewensohni, though a very vicious and aggressive ant, seems not to sting quite as severely as the Pseudomyrmas inhabiting 7\ 60 bulletin: museum of comparative zoology surinamensiSy. Tachigalia paniculata and the bull-horn Acacias. When the twigs or branches which it inhabits are split open their walls are found to be smooth and clean and of a dark brown color. To these walls the larvae are hung by means of their hooked, curved dorsal hairs and are fed with infrabuccal pellets like the larvae of other Pseudomyrminre. The latrines, which occur at intervals of several inches, are of much the same composition as described for A. menceps and longiceps, but moister and more glutinous. I found few Coccids in the internodes and at rather infrequent intervals. Instead of making pits, the ants gnaw narrow grooves one to three centimeters long and in these the Coccids lie in a linear series. They resemble the species cultivated by A. menceps but are smaller, suggesting that loewensohni, like Ps. baileyi, may occasionally devour them instead of using them as a perennial source of honey-dew. Most of my obser- vations on these ants, however, were made at the height of the dry season and while the trees were in flower or fruit, so that the small number of Coccids may also be due in part to less favorable trophic conditions. Since the larvse, pupse, males and winged females of loewensohni were not very abundant, it is probable that, like Ps. baileyi, it breeds more actively during some portion of the rainy season. This was indicated during the summer of 1924 by observations in the swamp at Marajal. Here the few colonies of loewensohni which I examined contained more brood and more numerous sexual forms and Coccids. The following miscellaneous organisms were found associated with T. americana or with its ant-inhabitants: Lepidoptera. Among the Heterocera there are at least five species that feed on the trees. One of these is identified by Dr. W. T. M. Forbes as a Thyridiid, the greenish caterpillar of which, nearly an inch long, is very common on the twigs, devouring the pith, tunnelling through the nodal partitions and depositing masses of coarse frass at intervals. This caterpillar is so common that it must be an impor- tant agent in facilitating the occupation of the twigs by the ants. Although pupse were obtained during the latter part of March I did not succeed in rearing the imagines. On the trunks of some of the trees at Balboa there were communal masses of cocoons, larger than one's fist. From these Mr. Zetek reared many specimens of both sexes of two handsome reddish brown Saturniid moths, which Mr. W. Schauss has identified as Hylesia hamata Schauss and H. darlingi Dyar. A large empty cocoon of another Saturniid was found attached wheeler: neotropical ant-plants and their ants 61 to the trunk of one of the trees and the case of a Psychid allied to Thyridopteryx to a twig. The following Rhopalocera, identified by Dr. Forbes, were taken at the Triplaris flowers at Balboa. (1) Junonia lavinia zonalis Felder. (2) Anartia jatrophm L. (3) Anosia plexippus L. (4) Anosia berenice Cram. (5) Antigonus (Systasea) erosus Huebn. (6) Hesperid (unidentified). Diptcra. The only members of this order taken were a small Trypetid which was swept from the flowers and a small Asilid occa- sionally resting on the trunk. Hymenoptera. The caterpillar of the Thyridiid above mentioned is parasitized by a small Hymenopterous larva which makes its cocoon in the twig cavity inhabited by the host. I failed to rear the imago. A single large red Ichneumonid was seen ovipositing in one of the cocoon-masses of Hylesia hamata, but escaped. The following were taken at the flowers: two Yespidae, Polistes canadensis L. and Enmenes nana Kirsch (J. Bequaert det.) and the folllowing eight bees, identified by Prof. T. D. A. Cockerell (1928):— (1) Megachile pocvlifera Ckll. (2) Apis mellifica L. (3) Apis mellifica var. ligustica Spin. (4) Melipona fulvipes subsp. triplaridis Ckll. (5) Melipona orbignyi subsp. phenax Ckll. (6) Trigona cupira F. Smith. (7) Trigona pectoralis D. T. subsp. panamensis Ckll. (8) Nannotrigona tcstaceicornis Lep. All but one of these are social bees. Coleoptcra. Three species of beetles taken at T. americana flowers at Balboa in 1923 were identified by Mr. H. S. Barber as Coscinoptera cingulata Lee. (Chrysomelid, several specimens), Hyporhagus laevi- punctatus Thom. (Monommid, several specimens) and Acanthoscelides sp. now (Bruchid, one specimen). The last has been reared by Mr. Bridwell from pigeon-peas and the description is in MS. Three other unidentified Coleoptera were observed at Balboa, namely some small larva?, possibly Curculionids devouring the pith in young twigs, quite a number of Coccinellid larvae on the foliage and evidently preying on the Coccids and a species of termitophilous Staphylinid living in considerable numbers in one of the nests of the termite cited below. 62 bulletin: museum of comparative zoology In 1924, five more Coleoptera were taken on the bark and leaves but were not identified (One small Coecinellid; one Curculionid, one Anthribid and two small Tenebrionids). Isoptera. Some of the trees at Balboa had large elliptical, ellipsoi- dal, black termitaria enveloping their trunks. The termites were identi- fied by Mr. Zetek as Nasutitermes comiger. A dead shoot at the base of one of the trees was inhabited by a species of Leucotermes. Orthoptera. Several small cockroaches determined by Mr. Hebard as Latiblatclla angustifrons Hebard, were found hiding between the walls of the Nasutitermes termitaria and the bark to which they were at- tached. Small oothecse which must have belonged to some other Blat- tid were occasionally found in the cavities of the twigs. Thysanoptera. A large black species with greatly incrassated an- terior femora was occasionally found in the twigs together with nymphal individuals. Heteroptera. Dr. R. F. Hussey has identified the following bugs taken from the foliage : Dysdercus ruficollis L. (Pyrrhocorid) Zelus sp. now near atripes Champ (Reduviid) Hypselonotus lineatus Stal. var. neglectus Horvath (Coreid) • Homoptera. An unidentified Aleurodid was occasionally seen on the leaves. The following Coccids have been identified by Dr. Morrison. (1) Akermes sp. On twigs. (2) Pscudococcus brevipes Ckll. In internodes with Azteca menceps. Las Cascades; with Crematogaster ludio at Miraflores. (3) Pscudococcus probrevipes Morr. In internodes with Azteca men- ceps near Miraflores; with Pseudomyrma loewensohni at Balboa. (4) Saissetia auriculata Morr. On twigs inhabited by Ps. loewen- sohni at Las Cascades. (5) Ceroplastes cirri pediformis Comst. (?) On twigs at Balboa. Araneina. The only spider seen was Eriophora edax Bl. (N. Banks det.), which was running on the bark. Acarina. The mites found in the latrines of Azteca menceps have not been identified. Nematodes. The nemas occurring in the latrines of the same ant are being studied by Dr. Cobb. Phaenogams. A large mistletoe (Struthanthus orbicularis H. B. K.) was found growing on two of the trees at Balboa. It is common on other trees in the Canal Zone. Cryptogams. Here belong the moulds and bacteria that flourish in the latrines of A. menceps and Ps. loewensohni. wheeler: neotropical ant-plants and their ants 63 Adding the 52 Arthropods cited in the foregoing list to the 16 differ- ent Formicidse we have 68 forms associated with T. americana and distributed as follows: Hymenoptera 28 Lepidoptera 11 Diptera 2 Coleoptera 11 Isoptera 2 Orthoptera 2 Thysanoptera 1 Heteroptera 3 Homoptera 6 Araneina 1 Acari 1 Total 68 The trees examined were much fewer in number than those of Cordia alliodora and I was unable to study any very young or seedling speci- mens. Nevertheless the number of insects infesting americana seems to be sufficient to corroborate the general conclusions derived from a study of Cordia alliodora. (D) Triplaris auriculata Meisner According to Standley (1922), this is probably the correct name for the tree which I called T. Macombii Donn. Smith in my paper of 1913. He records it as occurring in Chiapas "and perhaps elsewhere in Mexico". Donnel Smith's material was collected at Jiquilisco, Salvador. I did not at first recognize it as a Triplaris when I encountered it in January 1911 along the roadsides of Escuintla and Patulul in Western Guatemala. It is a larger tree than T. americana, attaining a height of at least 40 or 50 feet, with stouter trunk and more spreading branches and large, coarse, dark green, broadly ovate, short-petioled leaves. When first seen it was putting forth branches of long yellowish flower- spikes, covered with a deciduous sheath. The fruit, which I did not see, is described by L. Donnel Smith (1S94) as pale yellow. He has described (1895) a variety rufescens from Mayatinango, Guatemala, with brick-red flowers and more pilose leaves. My specimens seem to agree best with those of the typical Macombii in the Gray Herbarium. The twigs and branches are coarser than those of T. americana. Re- examination shows that the twigs have the same structure and are perforated in the same manner by the ants at the elliptical cleft areas, 64 bulletin: museum of comparative zoology which look like hypertrophied lenticels but are very probably formed as in other species of Triplaris by local dehiscence and subsequent healing of the expanding internodes. I have not since had an oppor- tunity to study auriculata which seems to have a rather restricted distribution. The following ants were collected in the internodes of the tree in 1911: Pseudomyrma sericea Mayr. var. ita Forel. Pseudomyrma sericea var. fortis Forel. Monomorium carbonarium F. Smith subsp. ebeninum Forel. Azteca prorsa Wheeler. Tapinoma ramulorum Emery subsp. inrectum Forel. Of these the Pseudomyrmas and Azteca are the most abundant and characteristic, the latter being, perhaps, peculiar to the plant (obligate). The Monomorium and Tapinoma occur also in the twigs of other trees. Cutting the branches of T. auriculata is decidedly painful owing to the Pseudomyrmas which, though they form smaller colonies, sting quite as severely as Ps. loewcnsohni. A. prorsa is closely related to A. piMieri, longiceps and menceps and seems to have very similar habits. It is timid and inoffensive. In order to complete my enumeration of the ants inhabiting Trip- laris, I may refer briefly to the records of those taken in undetermined species. The following have been cited in the literature merely as occurring in Triplaris or without further comment: (1) Psexidomyrma dendroica Forel. In hollow branches of Triplaris sp. Amazonas (E. Ule) (2) Pscudomyrma latinoda Mayr. Probably in Triplaris or Tachigalia. Brazil (J. Trail) (3) Pseudomyrma arboris-sanctw Emery. In Triplaris sp. Bolivia (Balzan, W. M. Mann); Peru (Staudinger) ; Amazonas and Matto Grosso (F. Silvestri) (4) Pseudomyrma arboris-sanctce var. cordobensis Forel. Probably in Triplaris. Argentina (C. Bruch) (5) Pscudomyrma arboris-sancta? var. rurrena-baquensis Wheeler. In Triplaris sp. Bolivia (W. M. Mann) (6) Pseudomyrma arboris-sancta? var. symbiotica Forel. In Triplaris (probably americana) Colombia (A. Forel; G. Salt) (7) Pseudomyrma sericea Mayr. var. rubiginosa Stitz. In Triplaris sp. Brazil (E. Ule) (8) Azteca brevicornis Mayr. var. boliviana Wheeler. In Triplaris sp. Bolivia (W. M. Mann) wheeler: neotropical ant-plants and their ants 65 Ps. dendroica and latinoda are closely related to arboris-sanctoe and triplaridis and undoubtedly have very similar habits. The Azteca was taken in the stems of a peculiar Triplaris which judging from Dr. Orlando White's herbarium specimens accompanying it, is quite unlike those with which I am acquainted. The only ant recorded from T. Schomburgkiana is Ps. dendroica- var. emarginata Forel, which was taken by Ule in Amazonas (see p. 164). Morteo, as we have seen (p. 47), records the occurrence of the common Oriental Dolichoderus (Hypoclinea) bituberculatus as living in T. americana when growing under cultivation in the East Indies. Omitting this ant, there are some 30 different Formicida? and more than 50 other organisms known to inhabit the hollow branches and foliage of the various species of Triplaris in different parts of the American tropics. Chapter 3. OBSERVATIONS ON TACHIGALIA The beautiful Caesalpinaceous trees of the genus Tachigalia are confined to Amazonas, Eastern Peru, the Guianas and Venezuela, and therefore have an even more restricted distribution than the species of Triplaris. About 20 species have been described, but the "Index Kewensis" recognizes only 13 as valid, and perhaps this number may be reduced when more material is available and the range of variation in the different forms has been thoroughly studied. The type species, at least, varies considerably even during its onto- geny, the juvenile form when growing in the shade having a very different habitus from the large tree exposed to the sun-light. The genus was established by Aublet as long ago as 1775 for a species, paniculata, which he found growing along the rivers of French Guiana. He named the plant Tachigalia from the Carib "tachigali", "tachi" being the name employed by the Indians of the Guianas and Brazil for the stinging ants of the genus Pseudomyrma, which regularly inhabit the enlarged petioles of Tachigalia as well as the internodal cavities of Triplaris. Part of Aublet's description of T. paniculata may be quoted: "The trunk of this tree rises to a height of fifty or sixty feet or more, with a diameter of three feet. Its bark is gray, rugose, its wood is hard and whitish. It produces at its summit a large number of stout branches which spread in all directions and are laden with twigs furnished with alternate winged leaves, with two rows of opposite leaflets, the greatest number of which is six on each side. They are firm, entire, terminating in a point, smooth and green above, grayish green beneath. Their petiole is very short, 66 bulletin: museum of comparative zoology articulated to a triangular swelling five inches long and terminating in a point, accompanied at its origin by two stipules which are soon deciduous. The largest leaflets are six inches long by two and a quarter inches broad. The flowers arise at the end of the twigs and are borne in large, long panicles, the stems of which are simple and covered with flowers throughout their length." The corolla is yellow and sweet-scented and the seeds are surrounded by a flat, elliptical wing or expansion. The tree flowers and fruits in April and November. Aublet described also a T. trigona, which proves, however, to be a synonym of paniculata. Tulasne (1844) redescribed paniculata and added six other forms, only two of which are now recognized as distinct, two, eriocalyx and sericca, being synonyms of paniculata. T. august) 'folia described by Miquel (1851) from Surinam also proves to be a synonym of Aublet's species. None of these botanists deigned to leave us any notes on the rela- tions of the Tachigalias to their ants. This was left to Spruce, who writes in his article submitted to the Linnean Society in 1869 but not published till 1908: "The Tachigalije are low-growing riparial trees, of black-water rivers, and have pinnate, often silky foliage; and small, yellow, sweet-smelling, nearly regular flowers disposed in panicles. All have trigonous petioles, which are mostly dilated at the base into a fusiform sac, tenanted by ants. T. caripes (recte cavipes, later regarded by Bentham (1870-76) as a variety of paniculata) grows abundantly on the banks and on inundated islands, of the Uuapes. It is a spreading tree of 30 feet, and has the ramuli, petioles and leaves clad with a fine, close, silky pubescence. The sacs of the petiole are inhabited by small black ants, whose entrance is by a little hole on the underside of the sac. T. ptychophysca sp. n. grows in moist sandy caatingas by the same river, and has a similar sac on the petiole." Ule (1907), in Amazonas and Eastern Peru, observed three species of Tachigalia, which were identified by Harms (1906) as formicarum Harms, paniculata Aubl. and spicata Aubl. The first, from Tarapoto, Peru, proved to be a new species and is a tree 30 meters high, with yellowish flowers. Its large petiolar sacs were inhabited by Pseudo- myrma latinoda Mayr subsp. tachigalias Forel. Ule states that "the ants live mainly in the petiolar sacs; in blooming and fruiting specimens they also settle in the axes of the large, hollow, swollen flower panicles. Only on one occasion, near Iquitos, did I observe that they had also perforated and taken possession of the twigs." wheeler: neotropical ant-plants and their ants 67 J. Huber (1909) described a T. macrostachya, which was collected by Ducke on the Rio Trombetas, Amazonas, and had its hollow petioles inhabited by Ps. latinoda var. endophyta Forel. In 1921 I gave a detailed account of T. paniculata and its inhabi- tants as observed by Professor I. W. Bailey and myself at Kartabo, British Guiana, and Professor Bailey (1923) has since published a description of the anatomical peculiarities of the plant. The reader may also be referred to my paper for an account of the ants, coccids and other organisms and especially of the very interesting social Silvanid beetles, Coccidotrophus socialis and Eunausibius wheeleri, which live in the petiolar cavities of the young trees before they are occupied by the ants. The following list includes all the known ants which I have found in the petiolar swellings of T. paniculata, together with those recorded by others as occurring in other species of the genus: (1) Neoponera crenata Roger. (T. paniculata) (2) Neoponera unidentata Mayr. (T. paniculata) (3) Pseudomyrma damnosa Wheeler (T. paniculata) (4) Pseudomyrma latinoda Mayr. var. coronata Wheeler (Tachigalia sp. ?) ' (5) Pseudomyrma latinoda var. endophyta Forel (T. macrostachya) (6) Pseudomyrma latinoda var. nigrescens Wheeler (Tachigalia sp.) (7) Pseudomyrma latinoda subsp. bradleyi Wheeler (Tachigalia sp.) (8) Pseudomyrma latinoda subsp. tachigalia^ Forel (T. formica-rum) (9) Pseudomyrma maligna Wheeler (T. paniculata) (10) Pseudomyrma maligna var. cholerica Wheeler (T. paniculata) (11) Pseudomyrma maligna var. crucians Wheeler (T. paniculata) (12) Pseudomyrma picta Stitz (Tachigalia sp.) (13) Pseudomyrma picta Stitz subsp. casta Wheeler (Tachigalia sp.) (14) Pseudomyrma sericea Mayr. var. rubiginosa Forel (Tachigalia sp.) (15) Phcidole cramptoni Wheeler subsp. petiolicola Wheeler (T. pan- iculata) (16) Phcidole (Hendeeapheidole) tachigalia Wheeler (T. paniculata) (17) Crematogaster (Orthocrema) delitesccns Wheeler (T. paniculata) (18) Crematogaster (Orthocrema) limata F. Sm. subsp. palans Forel (T. paniculata) (19) Solenopsis helena Em. subsp. hermione Wheeler (T. paniculata) (20) Solenopsis helena subsp. ultrix Wheeler (T. paniculata) (21) Leptothorax (Goniothorax) echi nai l i nodis Forel subsp. aculeatinodis Emery var. pleuriticus Wheeler (T. paniculata) 68 bulletin: museum of comparative zoology (22) Leptothorax (Goniothorax) umbratilis Wheeler (T. paniculata) (23) Azteca foveiceps Wheeler ( T. paniculata) (24) Azteca tachigalia; Forel (Tachigalia sp.) (25) Azteca traili Emery ( T. paniculata) (26) Brachymyrmex heeri Forel ( T. paniculata) (27) Brachymyrmex heeri var. basalis Wheeler (T. paniculata) (28) Camponotus (Myrmobrachys) pittieri Forel var. posnalis Wheeler (T. paniculata) (29) Camponotus {Myrmobrachys) zoc Forel (T. paniculata) Of these 29 forms probably the only ones that can be regarded as obligates are the various Pseudomyrmas and Aztecas, the remainder being merely inquilines which frequently nest in the cavities of other plants. Perhaps A. traili should be assigned to this latter group. In my paper on T. paniculata I gave a list of 28 miscellaneous organisms associated with the plant, its ants or its Coccids (Pseudococcus brevipes). Dr. Morrison (1922) has since described a second coccid, Ripersia petiolicola, which occasionally lives on the petioles but was not men- tioned in my paper. As known to date, therefore, the Tachigalia bioccenoses embrace more than fifty different organisms. The con- clusions which we reached as a result of our investigations are well summarized in the two concluding paragraphs of Professor Bailey's paper: "The hollow foliar axes of the ant-plant Tachigalia paniculata are colonized by at least seven "obligatory" guest insects. The domatia of juvenile plants are taken possession of by two extraordinary social beetles, but during the subsequent development of the plants these insects are dispossessed by ants. Both the beetles and the ants avail themselves of the structural peculiarities of their host plant in a singularly efficient manner. Not only do they make use of the hollow foliar axes as convenient nesting chambers, but they feed, either directly or indirectly, upon the softer tissues in the interior of the domatia, The beetles eat the parenchyma of the wide, primary medullary rays, utilize it in the construction of their puparia, and solicit and obtain liquid carbohydrates from herds of Coccids which graze upon it. The ants also feed upon this tissue vicariously through intervention of Coccids, and utilize it in the construction of carton partitions. "There, is no evidence to indicate that the structural peculiarities of T. paniculata are initiated by ants or by gall forming insects, or that they originated as adaptations for attracting a defending army of ants. The relations between the host plant and the beetles and the wheeler: neotropical ant-plants and their ants 69 ants are not those of a mutually beneficial symbiosis (Belt, Schimper), but an interesting type of parasitism, in which there is a remarkable parallelism in the behavior of representatives of such widely separated groups of insects as the Hymenoptera and the Coleoptera. The nesting and feeding habits of the insects, and their relations to the coccids, are largely determined by the structure and arrangement of the various vegetative tissues during different stages in the development of the petiole and rhachis. In studying the habits of phytophagous and plant inhabiting insects, it is evident that the anatomy of the host plants deserves more careful consideration than it has received heretofore." Chapter 4. OBSERVATIONS ON CECROPIA The trees of the Moraceous genus Cecropia have been much more carefully investigated than any other myrmecophytes. This is in part due to the fact that they are so abundant and are so readily recognized, because they contrast markedly with the remaining vegetation and especially at low altitudes constitute a very characteristic feature of the landscape. They are usually rather small or medium-sized trees, with smooth, pale-barked, slender trunk and branches, the latter few in number and arranged like the branches of a candelabrum and bearing large, coarse, long-petioled palmate leaves, which are usually silvery-white beneath. When moved by the wind the lower surfaces give a touch of vitality to what may be a rather monotonous background of vegetation. Writing of this feature of the Cecropias and of the coppery under surfaces of the leaves of the laurels and Chrysobalani along the Amazon, Spruce (1869, in 1908) says: "When my boat has been floating lazily in the water, under a burning and dazzling sun, with not a breath of air stirring, I have sometimes — as my eye wandered along the endless forest margin — given vent to some such exclamation as this "How tame and monotonous!" when the coming on of a squall, by simply revealing the glowing tints of the underside of the leaves, has in a moment waked up the scene into life and beauty." The Cecropias, unlike Cordia and Tachigalia, are dioecious and their inflorescence is inconspicuous, consisting in both sexes of bunches of compact green catkins, or aments. The trees are known to the natives of Brazil under the names "imbauba", "imbauva" "ambauva", "embaiba" or "ambay", to the Peruvian as "ceticos", to the natives of Central America as "guarumo", and to those of the Antilles as "llagrums" or "yagram". The British colonists in South 70 bulletin: museum of comparative zoology America call them "shakewood", "trumpet" or "drum" trees. The West Indians in the employ of the Panama Canal Zone refer to them as "trompies". In Brazil, according to Bequaert (Wheeler and Bequaert, 1929), "the Cecropias generally grow in dense grooves. Some of the species of the Amazonian Basin are commonly found in the second growth, in plantations, along roadsides and in waste-places. They may be observed right in the towns and sometimes grow out of the walls of old buildings. This would seem to indicate that the seeds are scattered in the excrement of birds and bats that feed on the fruit. Other species prefer the alluvial woods, or what is known in Brazil as "varzea", i.e. low-lying land that becomes water-logged when the rivers reach their highest level. Finally a few species thrive in the "igapo", or true inundated forest, and are the very first plants to colonize the shifting mud-banks in the river itself, as well as the new alluvial land. During much of the year these Cecropias stand in swiftly flowing water many feet deep, so that the ant-colonies that inhabit them must have their food-supply restricted to the food- bodies produced by the plant and the honey-dew furnished by the Coccids in their internodal cavities". My own observations in British Guiana, Mexico, Central America, Cuba and Porto Rico agree with Bequaert's account, except that in these countries there seem to be no forms adapted to amphibious conditions. Though the trees are sometimes found in moist places they are more frequent on the hills or mountain sides, either in small grooves or single and intermingled with the other plants of the jungle or hylsea. When man interferes with the natural conditions, the Cecropias behave as veritable tree-weeds and rapidly take possession of the newlv turned soil of railroad and ditch embankments, road- sides, clearings; etc. I was able to witness the occupation of such sites on a grand scale in Panama, during the building of the canal and relocation of the transisthmian railroad. Bequaert's suggestion that the seeds may be spread by birds and bats seems very probable. Of all the neotropical ant-plants the Cecropias are the most widely distributed. They are common throughout tropical Mexico, Central America, the Antilles and South America except Patagonia and parts of Argentina and in some of these regions often ascend to altitudes of four or five thousand feet. Although botanists have been sufficiently interested in the genus Cecropia to describe about 100 species, they have failed to give us "any adequate monograph or key to the various forms, so that their identification in the field is a matter of no little wheeler: neotropical ant-plants and their ants 71 difficulty. Moreover, as Bailey (1922, p. 371) has shown, the leaves of the same species undergo profound changes in form during ontogeny, and the specific characters are probably still further obscured by hybridization. Apparently only certain species are myrmecophilous, while others are never regularly inhabited by ants. There are also two genera, Pourouma, with about 20 species, and Coussapoa, with about 15 species, which are closely related to Cecropia and at least occasionally harbor ants, but our knowledge of these plants is very fragmentary. The association of ants with Cecropias has long been known. It was briefly described by Maregravius (1648), Piso (1658) and Ray (16S8) in the seventeenth century, but excited no further inquiry till 1874, when Belt recorded his observations in Nicaragua. Since that time a number of papers, wholly or in part devoted to the Cecropias and their ants have been published by Fritz Midler (1876, 1880, 1883), Schimper (1888), Schumann (1889), Warming (1894), Ule (1897, 1905, 1906), Rettig (1904), H. von Ihering (1907), Fiebrig (1909), Wheeler (1908, 1913), Bailey (1922) and Wheeler and Bequaert (1929). The papers of Miiller, Schimper, von Ihering and Fiebrig on C. adenopus L. and of Bailey on C. angulata are specially worthy of notice. A general description of the structure of the Cecropias is given in my ant-book (1910, p. 305-310) and is reproduced by Bequaert in his article on the myrmecophytes in my "Ants of the Belgian Congo (1922). Ule (1907) has also published a brief account which I trans- late: "All the Cecropias that harbor ants have essentially the same structure which Schimper has described in detail. The internodes of the branches and twigs are hollow and separated from one another by transverse partitions. Each internode possesses a leaf, and above it there is a groove which it produces by pressure of the petiole on the axial bud while it is still enclosed. In this groove there is always a pit. A similar shallow groove also occurs in other ant-plants, but the pit is peculiar to Cecropia. Now at this point the Cecropia is always perforated by the fecundated (Azteca) queen, and this is the more easily accomplished because the wall of the pit is thin and lacks fibrovascular bundles. After the queen has slipped into the cavity or chamber through the opening, the latter, as long as no workers are present, closes through the formation of callous tissue around its edges." Later the worker progeny of the queen again open the orifice and use it permanently as the entrance or exit to the internode. "The chambers which arise in the internodes in the place of the early disappearing pith are circular in cross-section, on an average 72 bulletin: museum of comparative zoology 4 to 7 cm. long and separated from one another by very thin fragile partitions, which are always perforated by the ants. In the interior of the chambers the ants build up a kind of labyrinth for their larvae out of a brown, wax-like substance probably derived from the Cecropia tree. As a rule each chamber is at first inhabited by only a single female, whose cell is often all it contains. In addition there are always white Coccids, on the saccharine excretions of which the ants in part subsist. But the insects are also afforded another source of nourishment by the plant itself, for at the base of each leaf-petiole there is a hairy cushion (trichilium) in which proteid-containing food- bodies sprout and are eagerly sought by the ants. These pear- or egg-shaped structures, called "Miillerian bodies", resemble insect-eggs. New bodies are being formed continually in the place of those carried away by the ants. Favored by these conditions, the ants increase enormously in numbers on the Cecropia trees and pass their lives in the crown of foliage. Of certain species of Cecropia nearly all the individuals, of others only occasional trees are inhabited by ants. In their earliest youth the Cecropias are usually free from ants; they are not invaded by fecundated queens till they reach a height of some meters. The trees exposed to inundation cannot, of course, harbor ants, because they are kept away by the water." The last remark is evidently incorrect, since the Cecropias standing in water, may be settled by Azteca queens reaching them before deflation. Moreover, the internodes of the trunk as well as those of the branches are inhabited by the ants, and Ule's statement in regard to the time of infestation of the young trees with the Azteca queens does not agree with my observations on many hundreds of plants. In British Guiana, Costa Rica, Guatemala and Panama I regularly found colony-founding queens in the internodes of all young trees, often in those only a foot or two feet high. Attention should also be called to the fact that Rettig has described another possible source of ant-food in the "pearl glands" on the leaves of the Cecropias. These structures are very similar to the Miillerian bodies of the trichilia and also contain proteids, oil and sugar. It is interesting to note that the first observer to call attention to the Coccids and their nutritive value to the Cecropia ants was Thomas Belt (1874, p. 222), though he overlooked their other important source of food in the Miillerian bodies. This is clear from the following passage: "The stem of the Cecropia, or trumpet-tree, is hollow, and divided into cells by partitions that extend across the interior of the hollow trunk. The ants gain access by making a hole from the wheeler: neotropical ant-plants and their ants 73 outside, and then burrow through the partitions, thus getting the run of the whole stem. They do not obtain their food directly from the tree, but keep brown scale insects (Coccidae) in the cells, which suck the juices from the tree, and secrete a honey-like fluid that exudes from a pore on the back, and is lapped up by the ants. In one cell eggs will be found, in another grubs, and in a third pupae, all lying loosely. In another cell, by itself, a queen ant will be found, surrounded by walls made of a brown, waxy-looking substance, along with about a dozen Coccidae to supply her with food. I suppose the eggs are removed as soon as laid for I never found any along with the queen ant. If the tree be shaken, the ants rush out in myriads and search about for the molester. The case is not like the last one (the bull-horn Acacia), where the tree has provided food and shelter for the ants, but rather one where the ant has taken possession of the tree, and brought with it the Coccidae; but I believe that its presence must be beneficial. I have cut down some dozens of the Cecropia trees, and never could find one that was not tenanted by ants. I noticed three different species, all, as far as I know, confined to the Cecropiae, and all farming scale-insects. As in the bull's-horn thorn, there is never more than one species of ant on the same tree." H. von Ihering described an exceptional condition in Azteca muelleri Emery which inhabits Cecropia adenopus. In this case the ants construct a large spindle-shaped carton nest in the bole of the tree. The nest is small at first and produces no deformation of the bole, but as the ants enlarge the structure they cut away more and more of the surrounding wood to convert it into carton and the weight of the trunk and crown above the nest causes the bole to bulge at the weakened zone so that the presence of the nest is indicated from the outside, von Ihering interpreted the enlargement which is not pro- duced by any other Cecropia-inhabiting Azteca, as a huge gall, but it is clear that it is nothing of the kind. Both Schimper and H. von Ihering found that one of the Brazilian Cecropias, C. hololeuca, lacks the trichilia and Miillerian bodies and is not regularly inhabited by ants, and Bailey found a similar absence of these organs in C. sciadophylla var. decurrens in British Guiana, though it is occasionally inhabited by non-obligate Formicidae. On the other hand, I found (1908) that a Porto Rican Cecropia, which I referred to C. peltata L. but which is probably C. Urbaniana Snetlage, possesses trichilia and coral red food-bodies, but is not inhabited by ants. I have made similar observations on the Cecropias of Cuba. In fact, the obligate Cecropia ants, the Aztecas, are absent from all 74 bulletin: museum of comparative zoology the West Indian Islands, except a few of the Windward group. It seems that Warming (1894, p. 185, Fig. 6) had previously noticed that the Cecropias of Aguadilla, Porto Rico, though not inhabited by ants, nevertheless possessed distinct but poorly developed trichilia. If I understand his remarks, he inferred that this might represent a degenerate condition due to the absence of the customary insect stimulation. Rettig (1904, p. 16, 21) states that von Meyer (Die Secretionsorgane der Pflanzen, Berlin, 1839) described trichilia in Porouma guianensis Aublet and growing among the hairs small granules obviously homologous with the Miillerian bodies of Cecropia. Bequaert (Wheeler and Bequaert, 1929) has recently compiled the following list of Cecropias definitely known to bear trichilia and to be myrmecophilous : (1) C. adcnopas Miquel (= C. peltata Vellozo, non Linne) of Brazil. Its normal ant-inhabitant, Azteca muelleri Emery, builds in its trunk the large carton nest and produces the swelling above described. In Paraguay, according to Fiebrig (1909), the tree is tenanted by a different species, A. alfari var. mixta, which causes no modification of the bole. (2) C. angulata Bailey. British Guiana (I. W. Bailey, 1922). (3) C. robusta J. Huber. Common along in the lower Amazon in woods that are frequently flooded. Stated to be myrmecophilous (J. Huber, 1910, p. 61). (4) C. bifurcata Huber. Lower Rio Purus, Brazil. Cited as myrme- cophilous (J. Huber, 1910, p. 62). (5) C. lortivirens J. Huber. Upper Rio Purus, Brazil (J. Huber, 1910, p. 63). (6) C. paracusis J. Huber. Lower Amazon. Myrmecophilous (J. Huber, 1910, p. 64). (7) C. distachya J. Huber. Vicinity of Para. Myrmecophilous (J. Huber, 1910/p. 65). (8) C. lyratiloba Miquel (C. paludosa Warburg). A swamp species of Southern Brazil which H. v. Ihering found inhabited by Azteca. It possesses trichilia. (9) C. sciadophylla Martius. This species is doubtfully myrme- cophilous since it possesses no trichilia at the base of the petiole. According to E. H. Snetlage (1923, p. 358), C. Juranyiana Al. Richter is merely a variety of C. sciadophylla. Another variety, described by Snetlage as var. decurrens, was recorded by Lie as inhabited by Azteca emeryi Forel. Tin's record may be due to an error or the ants may merely have occupied the hollow stems. Professor Bailey, who wheeler: neotropical ant-plants and their ants 75 observed the same var. decurrens near Kartabo, British Guiana, regards it as non-myrmecophytic. It lacks trichilia and food-bodies, although it possesses a prostoma. He occasionally found certain inquiline ants in the internodes, but no Aztecas. (10) C. riparia "Warburg", Snetlage (1923, p. 363). Brazil. This species is provided with trichilia at the bases of the petioles and Ule (1906) found the internodes occupied by Azteca alfari Emery var. aequilata Forel. (11) C. fidfolia "Warburg", Snetlage (1923, p. 365). Rio Acre, Brazil. The bases of the petioles bear trichilia and Ule mentions that the internodes are inhabited by Azteca minor Forel. (12) C. montana "Warburg", Snetlage (1923, p. 368), of Peru, has trichilia and Ule found it inhabited by Camponotus (Pseudocolobopsis) ulei Forel. (13) C. mexicana Hemsley. A number of ants were found by Ross (1909) in this species, although the bases of the petioles appear to lack trichilia. (14) C. leucocoma Miquel (= C. armaria Warburg). Manaos, Brazil. A true myrmecophilous species with trichilia and food bodies, as Bequaert (Wheeler and Bequaert, 1929) has shown. (15) C. obtusa Trecul. Rio Negro and Rio Branco, Brazil. Like the preceding species, a true myrmeeophyte. Studied by Bequaert (Wheeler and Bequaert, 1929). Bequaert remarks that many other species of Cecropia are known to possess trichilia, e.g., C. carbonaria Martius and Miquel, C. cyrto- stachya Miquel, C. Dielsiana Snetlage, C. Engleriana Snetlage, C. Francisci Snetlage, C. Glaziovii Snetlage, C. leucophoea Poppig and Miquel, C. multi flora Snetlage, C. palmata Willdenow (perhaps the same as C. obtusa Trecul), C. sazatilis Snetlage, C. Ulei Snetlage and C. Urbaniana Snetlage. Some botanists assume that all such species are ant-plants. It is, however, by no means certain that the presence of trichilia alone is sufficient to give them the status of myrmecophytes. This is shown by my observations on the Cecropias of Porto Rico and Cuba. A detailed field and taxonomic study of many more of these trees will have to be made before we shall be able to give a satisfactory account of the prevalence and meaning of myrmecophily in the genus. The ants at present known to nest in the various species of Cecropia, Pourouma and Coussapoa are enumerated in the following list: (1) Neoponera stipitum Forel. In branches of Cecropia sciadophylla var. decurrens. British Guiana (Wheeler). 76 bulletin: museum of comparative zoology (2) Pseudomyrma ulei Forel. In twigs and branches of Coussapoa sp. Amazonas (E. Ule). (3) Pheidole guildini-muelleri For. subsp. avia Forel. In trunk of Cecropia adenopus. Brazil (Luederwaldt) . (4) Solenopsis saevissima F. Sm. In dry branch of Cecropia sp. Brazil (Luederwaldt). (5) Cremaiogaster (Orthocrema) quadriformis Mayr. In C. adenopus with Azteca muelleri. Brazil (Luederwaldt). (6) Cremaiogaster (Ortliocrema) limata F. Sm. In internodes of C. angulata Bailey and C. sciadophylla var. decurrens. British Guiana (Wheeler). (7) Cremaiogaster sp. In dead wood of C. adenopus with young colonies of Azteca muelleri. Brazil (H. von Ihering) . (8) Wasma7inia iheringi Forel. In small nest constructed on a Cecropia leaf. Brazil (H. Luederwaldt). (9) Cephalotes atraius L. In large branch of C. sciadophylla var. decurrens. British Guiana (Wheeler). (10) Cryptocerus pu.sillus Klug. In dry branch of Cecropia sp. Brazil (Luederwaldt) . (11) Cryptocerus sp. In dead wood of C. adenopus. Paraguay (Fie- brig). (12) Azteca alfari Emery. In Cecropia sp. Costa Rica (A. Alfaro, Wheeler) ; Panama (Champion); Venezuela; Colombia (Forel). (13) Azteca alfari var. cequalis Forel. In Cecropia sp. Brazil (A. Goeldi); Mexiana Island (Hagmann); Colombia (Lallemand). (14) Azteca alfari var. cequilata Forel. In C. riparia Warb. Brazil (E. Ule, A. Goeldi, J. Huber). (15) Azteca alfari var. arrentina Forel. In C. adenopus. San Ignacio, Missiones, Argentina (L. Hauman). (16) Azteca alfari var. curtiscapa Forel. In Cecropia sp. Panama (Christophersen, Wheeler) . (17) Azteca alfari var. fumaticeps Forel. In C. mexicana. Mexico (Ross). In Cecropia sp. Guatemala (Wheeler). (18) Azteca alfari var. langi Wheeler. In Cecropia sp. British Guiana (H. Lang). (19) Azteca alfari var. mixta Forel. In C. adenopus. Paraguay (Fiebrig); C. lyratiloba Miq. Brazil (Luederwaldt); C. leuco- coma Miq. Brazil (Bequaert). (20) Azteca alfari var. ovaiiceps Forel. In C. lyratiloba Miq. Brazil (Luederwaldt); In Cecropia sp. Brazil (Goeldi, Bequaert). wheeler: neotropical ant-plants and their ants 77 (21) Azteca alfari subsp. cecropia? Forel. In C. lyratiloba. Brazil (Luederwaldt) , C. obtusa Trecul. Brazil (Bequaert); C. "pel- tata" Dutch Guiana (G. Stahel) ; British Guiana (H. E. Box) ; Cecropia sp. (Goeldi, Huber and Ule); in "swamp Cecropia" Brazil (H. v. Ihering). (22) Azteca alfari subsp. lucida Forel. In Cecropia sp. Guatemala (Champion; Wheeler). (23) Azteca alfari subsp. lucidula Forel. In C. angulata Bailey. British Guiana (Wheeler); C. "peltata" Trinidad (Wheeler); Cecropia sp. Guatemala (Wheeler). (24) Azteca alfari subsp. lucidula var. zonalis Wheeler. In Cecropia sp. Panama (Wheeler). (25) Azteca alfari subsp. tuberosa Forel. In Cecropia sp. (probably) Brazil (Diaz da Rocha). (26) Azteca bicolor Emery subsp. belli Emery. On trunks of C. "pel- tata ,, Trinidad (Wheeler). (27) Azteca coeruleipennis Emery. In Cecropia sp. Costa Rica (Alfaro; Wheeler) ; Guatemala (Champion) ; Mexico (Schumann) ; C. mexicana Mexico (Ross). (28) Azteca constructor Emery. In Cecropia sp. Costa Rica (Alfaro, Tonduz, Pittier) ; Guatemala (Wheeler) ; Panama (Christopher- .sen, Wheeler); in C. "peltata", Trinidad (Wheeler). (29) Azteca constructor var. guianw Wheeler. In C. angulata Bailey. British Guiana (Wheeler). (30) Azteca coussapooe Forel. In branches of Coussapoa sp. Amazonas (E. Ule). (31) Azteca delpini Emery. In Cecropia sp. (probably) Matto Grosso, Brazil (Germain). (32) Azteca delpini var. trinidadensis Forel. In C. "peltata" . Trinidad (Wheeler) . (33) Azteca delpini subsp. antillana Forel. On Cecropia sp. Castries, St. Lucia (Wheeler, J. C. Bradley). (34) Azteca delpini subsp. antillana var. guadeloupensis Forel. In Cecropia sp. (probably) Guadeloupe (Forel); Roseau, Domi- nica (F. Lutz). (35) Azteca duroia: Forel. In branches of Pourouma sp. Amazonas (E. Ule). (36) Azteca emeryi Forel. In Cecropia sciadophylla Mart. Amazonas (E. Ule). (37) Azteca foreli Emery. In Cecropia sp. Costa Rica (Alfaro, Wheeler) ; Guatemala (Wheeler). 78 bulletin: museum of comparative zoology (38) Azteca foreli Emery var. eiserii Pergande. In Cecropia sp. (prob- ably mexicana) Colima, Mexico (Townsend). (39) Azteca foreli subsp. championi Forel var. breviscapa Forel. In Cecropia sp. Costa Rica (Tonduz). (40) Azteca foreli subsp ursina Forel. In Cecropia sp. Trinidad (Wheeler) . (41) Azteca instabilis F. Sm. In Cecropia sp. (Mexico, Colombia, French Guiana, Central America) ; in Cl angulata Bailey. British Guiana (Wheeler). (42) Azteca lanuginosa Emery. In C. Moleuca Miq. Brazil (Lueder- waldt) In C. adenopus Brazil (H. von Ihering) ; in carton nests on Crecropia sp. (W. Ehrhardt) . (43) Azteca minor Forel. In C.fidfolia Warb. Amazonas (E. Ule). (44) Azteca muelleri Emery. In C. adenopus Brazil (F. Miiller, Hetschko, H. von Ihering, Luederwaldt, J. C. Bradley). (45) Azteca schimperi Emery. In carton nest on C. leucocoma Miq. Manaos, Brazil (Bequaert). (46) Azteca sericea Mayr. In Cecropia sp. Costa Rica and Guatemala (Wheeler). (47) Azteca, trigona Forel subsp. mathildce Forel var. spuria Forel. In Cecropia sp. British Guiana (Wheeler). (48) Azteca trigona subsp. mediops Forel. In C. angulata Bailey. British Guiana (Wheeler). (49) Azteca ulei Forel var. gibbifera Forel. In trunk of Cecropia sp. Brazil (Luederwaldt). (50) Azteca ulei subsp. nigricornis Forel. In C. adenopus. Brazil (Luederwaldt). (51) Azteca xanthochroa Roger. In Cecropia sp. Costa Rica (Alfaro, Schwarz and Barber); Guatemala (Wheeler); in C. mexicana. Mexico (Ross). (52) Azteca xanthochroa var. costaricensis Wheeler. In Cecropia sp. Costa Rica (Alfaro). (53) Azteca xanthochroa subsp. australis Wheeler. In Cecropia sp. (very probably), Peru (Staudinger). (54) Azteca xanthochroa subsp. salti Wheeler. In Cecropia sp. Col- ombia (G. Salt.) (55) Azteca xanthochroa subsp. isthmica Wheeler. In Cecropia sp. Panama (Wheeler). (56) Camponotus (Tancemyrmex) bonariensis Mayr. In dead wood of C. adenopus. Paraguay (Fiebrig). wheeler: neotropical ant-plants and their ants 79 (57) Camponotus (Tancemyrmex) melanoticus Emery var. hagmanni Forel. In C. sciadophylla var. decurrens. British Guiana (Wheeler). (58) Camponotus (Myrmothrix) balzani Emery. In dead branches of C. adenopus. Brazil (H. von Ihering). (59) Camponotus (Myrmothrix) rufipes Fabr. subsp. renaggeri Emery. In dead wood of C. adenopus. Paraguay (Fiebrig). (60) Camponotus (Myrmobrachys) canescens Mayr. In trunk of C. adenopus. Brazil (Luederwaldt). (61) Camponotus (Myrmobrachys) vezenyi Forel. Occasionally in dead wood of C. adenopus. Paraguay (Fiebrig). (62) Camponotus (Pseudocolobopsis) ulci Forel. In C. montana Warb. Peru (E. lie). Probably all the ants in this list, except the Aztecas, are to be regarded as merely occasional inhabitants, or inquilines. And even among the Aztecas only certain species would seem to be really obligatory tenants of the plants — namely A. alfari, delpini, coerulei- pennis, constructor, muelleri and xanthochroa. Of these A. alfari is the Cecropia ant par excellence. Its geographical range is almost coextensive with that of the plants. It is represented by some 14 different varieties and subspecies, ranging from Mexico to Paraguay and Argentina, and is known to inhabit at least six or seven different species of Cecropia. No doubt further collecting will add considerably to the number of recognizable forms of this highly variable insect. While the earlier observers, Fritz Miiller and Schimper, were inclined to regard the Aztecas as the protectors of the Cecropias against the attacks of the Attini, or leaf -cutting ants, all the more recent authors, including H. von Ihering, Rettig, Fiebrig, Ule, Bailey and myself, have come to see in the Attini no such menace to the life or well-being of the plants. The various arguments in support of this contention have been set forth in detail, especially in the con- tributions of von Ihering, Fiebrig and Bailey, and need not be re- peated here. That the Cecropias are centers of important biocoenoses consisting of a great number and variety of organisms, some of which are far more injurious than the Attini, was first shown by Fiebrig in his study of C. adenopus in Paraguay. A conspectus of the forms he recorded together with additions by von Ihering, Bailey, Zetek and others, is given in the following paragraphs: Mammalia. Fiebrig mentions apes and bats (Phyllostoma sp.) as eagerly feeding on the fruit of C. adenopus. The most important mammal, however, is the sloth, Bradypus tridactylus L., which accord- 80 bulletin: museum of comparative zoology ing to Bates, H. von Ihering and others regularly devours the foliage and is not molested by the Aztecas. The sloth's relation to the tree is, in fact, so constant and so well known to the natives that the name "imbauba" and its derivatives really mean "sloth tree". Menegaux (1909), in his monograph of the genus Bradypus, states, on the authority of Geay, that the sloth feeds only on Cecropia leaves and cites Gmelin (1788), who says that B. tridactylus "victitat foliis teneris imprimis Cecropia?, non bibit, imbre metuit." Observations on the sloths at the Barro Colorado and Kartabo laboratories confirm this statement in regard to the feeding habits of the animal. Aves. Fiebrig mentions doves as occupying the adenopus trees and feeding on their ripe fruit and woodpeckers as devouring the Heliothis larva? {vide infra) which live in the twigs and branches. He also observed birds' nests among the foliage and figures one of them. Lcpidoptcra. No less than six different moths and butterflies feed as larva? on the large leaves of the Cecropias: (1) Gynaecia dirce L. The caterpillars of this beautiful Nymphalid were found feeding in great numbers on Cecropia at Ancon by Mr. Zetek. They are black with branched orange-colored spines. The pupa is gray and provided with two broad horns at the anterior end. Gundlach (Wolcott, 1923) had previously noted the same habit of the caterpillars in Porto Rico: "la oruga vive debajo de hoja de Cecropia, comiendo las nervosas gruesas." (2) Historis orion Fabr. Mr. Zetek also found the caterpillars of this Nymphalid devouring the foliage of the Cecropias at Ancon and reared the butterflies. The caterpillar is described by Wolcott (1923) as flattish, medium gray, with white saddle and states that Gundlach notes its occurrence on C. peltata in Porto Rico ("la oruga se crea en la Cecropia). (3) The Syntomid moth, Correbidia tcrminalis Walker, is cited by Wolcott from Porto Rico with the following note by Gundlach: "vive en la cara inferior de las hojas de Cecropia, formando luego im capullo poco primeroso." (4) The Dioptid moth, Diops ocellata Cr., is another Cecropia pest which was observed by Fiebrig in Paraguay. "The hairy larva of Diops ocellata Cr., devours the large leaves. It is not easily detected on the white-felted undersides on account of its chalk-white, black dotted coloration. I often found this larva, which reaches a length of 4 cm., in considerable numbers on a tree." (5) Fiebrig describes another moth caterpillar (undertermined) "of respectable dimensions" as living in the cambium layer of the C. wheeler: neotropical ant-plants and their ants 81 adcnopus trunk. The pupa "rests beneath the bark, which at one point is perforated by a T-shaped slit that enables the beautiful chocolate brown and sulphur-yellow moth to escape. The injury to the tree caused by this caterpillar is probably unimportant." (6) Heliothis sp. Fiebrig also describes in detail the habits of an undetermined boll-worm. He says: "The third caterpillar which I observed on Cecropia belongs to the moth 7584 (Heliothis sp. in litt.) and is unquestionably the most interesting. It competes with the Azteca (alfafi var. vii.xta) and lives in the younger portions of the twigs, precisely where the Dolichoderine is encountered. Such cater- pillar-infested twigs are extremely common at all seasons of the year. At certain times I found them on nearly every tree I examined and in large trees with 60-SO main and accessory twigs I have found 30-50 of them occupied by the twig-mining caterpillars." After describing the perforation of the twigs by the woodpeckers which feed on the caterpillars, Fiebrig continues: "I was long uncertain in regard to the time and place of the caterpillar invasion till I succeeded in finding their youngest stage, scarcely more than a millimeter long, in company with the Aztecas that were just founding their colonies in the uppermost chambers! Here I detected the obviously just hatched caterpillar in the completely closed internodal cavity beside the egg-laying ant-queen with her eggs and larvae and embedded in and evidently feeding on a damp brown mass of pith which had been chewed up by the mother ant. On several occasions also I found these small caterpillars up to a length of 6 mm. in the initial chambers of both young and older trees and repeatedly in company with just- emerged Azteca workers. Later, however, when, after perforation of the dissepiments, a greater portion of the twig becomes habitable by the ants, the caterpillars and ants were no longer observed in one anothers' company. Often, indeed, I found them separated, the Azteca being in the outermost tip of the twig and the caterpillar below, shut off by an intact dissepiment. While, therefore, at first the ant and caterpillar live peaceably side by side— a condition the more remarkable, because the small, large-headed, strongly man- dibulate caterpillars differ so markedly from the white, nearly naked Azteca larvae in their darker color and habitus, and especially in pos- sessing stiff bristles — later the "pugnacious" ants, which move upwards towards the tips of the branches, followed by the caterpillars, never- theless leave the latter in full possession of the Cecropia twigs. Since we cannot suppose that the soft-skinned caterpillars are aggressive, we shall not be mistaken in inferring that the ants are driven out 82 bulletin: museum of comparative zoology by the masses of caterpillar frass, often spun together, which plug up the chambers and render them uninhabitable. It is also possible that the caterpillars, which are capable of emitting considerable mucus, may use their silk as a means of defense. Only after the caterpillars have completely eaten out the ambay twig, does one of their number about to pupate, gnaw a large hole in the wall of the twig at one of the former ant-entrances. This opening is used as an exit not only by the individual that made it but also by all the other moths that develop in the twig! "It would seem, therefore, that the Heliothis caterpillars in their younger stages are synceketes of the Azteca, that after hatching from eggs laid by the mother moth on the outer surface of the plant, they probably enter the internodes through the perforations made by the nest-founding queens and that later the peculiar habits of the caterpillar render any further syncecetism with the ants impossible. It is probable that this same Heliothis larva was observed by Schimper (1888). At any rate, his Fig. 3, PI. II, shows a similar caterpillar lying on a large mass of frass in a > young adenopvs internode just above a cavity inhabited by Azteca. (7) Another undetermined Lepidopteron caterpillar is mentioned by H. von Ihering in Eastern Brazil. Hymenoptera. The following Chalcidids, Vespids and Apids have been found associating with Cecropias or their ants: (1) Conoaxima affinis Brues (1922). This Chalcid was described from a specimen which I took in a Cecropia internode (not in an Acacia spine, as stated by Brues!) at Quirigua, Guatemala, in 1911. I have since taken both sexes of the species at Balboa, C. Z., and have seen the larva? in various stages devouring the young colony- forming queens of Azteca alfari subsp. lucidula var. canalis. (2) Conoaxima azteeicida Brues. The habits of this species, which was taken in 1920 by Professor Bailey in internodes of C. angulata at Kartabo, B. G., are the same as those of the preceding species. The larva? were found destroying the young nest-founding queens of A. constructor and A. alfari. Professor Bailey's observations are re- corded in the following note: "Although many of the successive inter- nodal cavities of each young plant become inhabited, few of the queens succeed in raising a brood. When the stems are cut open, most of the chambers are found to contain dead queens. I was unable to account for this high mortality until I discovered the presence of a small scar in the callus which fills the entrance aperture. This scar within a scar indicated, of course, that some insect had emerged since the queen became sealed within her domatium. Following up this clue, I soon wheeler: neotropical ant-plants and their ants 83 found chambers — with modified callus in the apertures — which con- tained, in addition to the dead and frequently dismembered queen, the larva, pupa, or imago of a Hymenopterous parasite. The evidence at hand seems to indicate that the queens are parasitized before they enter their dwellings." (3) Conoaxima sp. A specimen of an undescribed species of Cono- axima was recently found by Dr. George Salt in the topmost internode of a young Cecropia at Vista Nieve, at an altitude of 5000 ft. in the Sierra Nevada de Santa Marta, Colombia. The internodes of the plant, which was only about 6 ft. high, were occupied either with soli- tary nest founding queens of a new subspecies of Azteca xanthochroa Roger, which I have called salti, or lower down with young colonies consisting of queens with brood or with brood and small workers. In the internode containing the Conoaxima was a mouldy mass, in all probability the remains of an Azteca queen that had been devoured by the parasite. (4) H. von Ihering mentions a rather large Chalcid which he found in the midst of ants {Azteca muelleri) in C. adenopus at Alto da Serra, Brazil. In all probability the insect was one of the Eucharidse, many species of which are known to parasitize ant-larva?. (5) The Cal verts (1917) found on one of the branches of a Cecropia in Costa Rica a large pendent paper-covered nest which was occupied by an active colony of wasps (apparently some species of Polybia) for at least four months. (6) Triaona sp. At Kartabo, B. G. Professor Bailey discovered a colony of a very small stingless bee, which Professor Cockerell has identified as an undescribed species, near goeldiana, in the internodes of a branch of Cecropia angulata. This nest is figured in my "Social Life among the Insects (1923). The same bee was also found nesting in a hollow liana. Diptcra. The following five Diptera seem in their larval stages to be either scavengers in decomposing portions of the Cecropias or para- sites of leaf-eating species. (1) Great numbers of a Tachinid fly were bred by Mr. Zetek from the pupa? of the Chrysomelid beetle, Coelomera caycnnensis Fabr. {vide infra), which feeds on the foliage of the Cecropias at Ancon, C. Z. (2) H. von Ihering bred a species of Drosophila from larva? living in matter derived from the decomposition of vegetable excrescences in an internode of C. adenopus. (3) Prof. Bailey bred numbers of a species of Drosophila from the male aments of C. angulata at Kartabo, B. G. 84 bulletin: museum of comparative zoology (4) von Ihering mentions slender Dipteron larvfe in soft, gelatinous excrescences in the upper internodes of C. adenopus. (5) Fiebrig found the moist frass masses of the Heliothis caterpillars described above to contain Dipteron larva?. Colcoptera. Some six or eight different beetles have been found to attack Cecropias: (1) A small unidentified Bostrichid, according to Fiebrig, feeds not only on the dead twigs of C. adenopus but often also on the green internodes inhabited by the Aztecas. The female beetles lay their eggs in the fresh cambium and the hatching larva? completely destroy this layer and also bore into the wood. (2) Fiebrig found a Cerambycid which bores both in the dry twigs and in the wood of the trunk. (3) Coclomera cayennensis Fabr. According to H. von Ihering, this Chrysomelid and a similar but smaller species lay their eggs on the leaves of C. adenopus and there undergo their entire development. "The larva? gnaw away the upper layers of the leaf but are never molested by the ants, notwithstanding their great injury to the foliage." Mr. Zetek has found this same beetle in all stages on the Cecropias at Ancon, C. Z. and has bred from its pupa? numbers of Tachinid flies (vide supra). The full-grown larva? measure about 15 mm. and have the abdominal segments provided laterally with blunt-spines and the last segment developed as a large, rugulose, shovel-shaped organ. They are opaque blackish with the head, prono- tum, legs and several tuberculate spots on the dorsal surface of each abdominal segment, except the last, dull orange yellow. Most of the larva? pupated January 16, the pupa? being naked and attached to the leaves by their posterior ends. The imaginal beetles, which emerged February 20, have opaque black elytra, with the remainder of the body more shining and of a dirty fulvous tint, except the antenna?, tibi?e, tarsi and venter, which are black. The Cecropias are very probably the true host plants of this beetle, which has very nearly the same geographical distribution. It was originally described from French Guiana. In the Bowditch Collection of Chrysomelida? in the Museum of Comparative Zoology I have seen specimens from Peru, Colombia, Venezuela, Bolivia, Panama, Yucatan and Rio de Janeiro, Brazil. (4) Fiebrig mentions a Chrysomelid, possibly C. cayennensis or an allied species, as feeding on the leaves of C. adenopus in Paraguay. (5) He also mentions a very common Chrysomelid larva, evidently one of the Cassidina?, as feeding in dense droves on the foliage. It wheeler: neotropical ant-plants and their ants 85 possesses a blackish brown, ehitinous, disk-shaped process, which it holds over its back when disturbed, like the similar processes, often covered with fieces, seen in other members of the group. (6) The larva of a Hispidine Chrysomelid, according to Fiebrig, often mines the lobes of the leaves in succession, surrounding each with a gallery and eventually pupating and completing its develop- ment in a boss-shaped gall at the base of one of the lobes. (7) A small yellow Curculionid is said by Fiebrig to visit the catkins. (8) Great numbers of small Curculionids, possibly allied to the preceding species, were found by Professor Bailey in the male aments of C. angulata at Kartabo, B. G. Orthoptera. Fiebrig observed Mantids and migratory locusts on the foliage of C. adenopus. The latter almost completely defoliated whole groups of the trees in the course of a few hours. Thysanoptera. Very common, according to Fiebrig, on the under surfaces of the leaves. Heteroptera. Fiebrig records several Lygseids, especially a pale brown and a delicate white species, as infesting the lower surfaces of the leaves, and a stout brown Pentatomid which guards its eggs on the foliage. All three of these bugs are extremely common and may occur on the same tree. They are in all probability very injurious. Homoptera. Fiebrig mentions a prettily colored Jassid as being common in all stages on the leaves. He also found an aphid and a pinkish Coccid living with the ants in the internodes. Wolcott (1923) records Aphis gossypii Glover as occurring on the leaves of C. peltata at Lares, Porto Rico. Acarina. A species of mite is recorded by Fiebrig as occurring among the Thysanoptera on the undersides of the leaves of C. adenopus. Nematoda. A Tylenchus-like form was found by Fiebrig living among the moist detritus left by the Heliothis larva? in the twigs. Fungi. Moulds occur in the same situation as the Nematodes and are often found covering the bodies of young queens that have died in the internodes before establishing colonies. This list comprises some forty different organisms, mostly associated with a single species of Cecropia (adenopus). Fiebrig states that he has omitted a number of forms and remarks: "When I compare them with the Hexapods occurring in Paraguay on other plants, it seems to me that the ambay is more thoroughly infested than the great majority of the woody plants of the region, and this the more astonishing, because its leaves are not enticing nor juicy and because the tree might seem 86 bulletin: museum of comparative zoology to be protected from most of its enemies by the peculiar properties of its sap." Among the organisms enumerated in the foregoing list the Coccids occupy a constant and privileged position. All those who have studied the Cecropias carefully — Belt, Fritz M tiller, Schimper, Warming, H. von Ihering, and Fiebrig — have noticed these insects and all, with the exception of Fiebrig, have regarded them as an important source of food for the Aztecas. Fiebrig's assertion that they "have no direct relations with the ants" must be attributed to faulty observation. Recently Professor Bailey has devoted special attention to the Cecro- pia coccids and has made some observations of interest in connection with the species occurring in other myrmecophytes. I quote from his paper (1922, p. 388) which owing to its publication in a botanical journal, may be readily overlooked by entomologists: "Having found a very close and significant relation between ants and coccids in most Ethiopian ant-plants, I devoted particular attention to the investiga- tion of their behavior in C. angulata. I did not succeed in finding a single large, ant-inhabited specimen which did not contain numerous coccids. When a tree is split open the ants are as solicitous for the wel- fare of the coccids as they are for that of their eggs, larvae and pupae. They seize them in their mandibles and carry them about until some unopened portion of the plant is found where they may be deposited in safety. In artificial nests, the workers spend hours in tending and stroking the coccids, and in feeding upon their sugary exudates. In view of these facts, it cannot be doubted that the miniature milch cows are an important source of liquid carbohydrates for the ants. "As in many of the African myrmecophytes the ants excavate pits in the walls of their domatia which enable the coccids to reach and feed upon the softer tissues of the Cecropia. Such excavations are essential, owing to the fact that the internodal, medullary cavity is entirely jacketed by a dense, horny layer of sclerenchyma. In the African ant-plants, the ants cut through to the cambium and induce the formation of a nutritive callus. In C. angulata the pits are not located in the sides of the internodal chamber, but in the nodal dia- phragms. At the time when the ants begin their excavations, the nodal partition consists of five distinct layers. The soft internal layer, which is provided with strands of conducting tissue and which is fed upon by the coccids, is separated from the external layers of porous, medul- lary tissue by two layers of dense, thick-walled tissue. The ants re- move the two external layers and cut circular pits in the underlying sheets of horny sclerenchyma. The coccids sit in these pits and thrust wheeler: neotropical ant-plants and their ants 87 their setae into the succulent tissue which is thus exposed. That the pits are not made by the coccids, as suggested by von Ihering is indicated, not only by the fact that the delicate sucking mouthparts of these insects are not adapted for excavating in dense tissues, but also by the fact that I have actually observed the ants in the process of excavating them." The preceding account of the Cecropias shows that the general picture of their relations to the ants is very similar to those of other myrmeeophytes with hollow or fistulose stems or petioles, such as the Cordias, Tachigalias and Triplarises, but there are two peculiar- ities, the preformed pit, or prostoma of the internodes and the Mullerian bodies, which have been repeatedly cited by authors as irrefutable proof of the adaptation of the trees to the Aztecas. The prostoma, however, is now generally conceded to be merely a deepening of the groove, or rill formed by pressure of the axillary bud. Prof. Bailey found that as a rule no pit is present in C. angulata, but merely a broad groove, whereas in C. sriadophylla var. decurrens, which is not inhabited by Aztecas, the thinning' of the internodal wall in the groove is much greater than in angulata. "Such facts as these,", he says, "suggest that the so-called prostoma of C. adenopus, and of other myrmecophytic species of Cecropia, is not an adaptation for attracting ants, but is merely a structural peculiarity, produced by the pressure of the axillary bud, which is utilized by the ants in their parasitism upon the plants." There remain then only the Muellerian bodies and possibly the pearl glands to support the view that the Cecropias have developed specific attractions or inducements for the ants. But the botanists have recently also cast doubts on the finalistic interpretation of these structures. The matter is well summarized in the following passage from Professor Bailey's paper (1922, p. 387) : "These small bead-like structures, which are packed with fat and protein, are formed in large numbers in a curious cushion or mat of hairs situated at the base of each petiole. The ripe food bodies are so assiduously collected by the ants that it is almost impossible to find one in situ, except in young uninhabited plants. Indeed, the ants frequently trim away the surrounding hairs and dig out the immature food bodies. Schimper interpreted these so-called Mullerian corpuscles, and similar structures which occur on the leaflets of certain myrmecophytic species of Acacia, as metamorphosed glands or highly specialized allurements for attracting ants. Rettig and others, however, have called attention to the fact that such glands occur on plants that 88 bulletin: museum of comparative zoology are not frequented by ants, and it is difficult for the adherents of myrmecophily to account for such occurrences without resorting to the purely gratuitous assumption that they are survivals from former symbioses. Ule is of the opinion, in addition, that the expenditure of carbohydrates and nitrogenous substances, contained in these corpuscles, is not compensated for by the protection which the ants afford to the plants." Chapter 5. NOTES ON RUBIACE^E AND VERBENACE^ Of all the families of plants the Rubiacese comprise the greatest number of myrmecophytes, but curiously enough, nearly all of these are paleotropical. From the Neotropical Region only a few species of Duroia, Remijia and Patima are known to be associated with ants. Though the genera Randia, Uncaria, and Psychotria occur in both hemispheres, and in Africa and New Guinea comprise some note- worthy ant-plants, none of the American species, so far as known, has developed this peculiarity. (A) Duroia and Remijia The genus Duroia, which is confined to the Amazonian region and northern South America, includes 10 species, three of which are known to be myrmecophilous, namely D. hirsuta Poppig and Endlicher, petiolaris J. D. Hooker and saccifera (Martius). The last is provided with a pair of peculiar sac-shaped domatia at the bases of the leaf-blades; the other species have no such structures but instead present swollen internodes which are inhabited by ants. A fourth species, D. dioica Karsten has similar swollen internodes but these are not definitely known to be inhabited by ants. Only one of the 14 known species of Remigia, R. physophora Bentham, is myrmecophilous and like D. saccifera possesses a pair of pouches at the leaf-bases. Spruce (1869, in 1908, p. 396) has the following notes on Duroia saccifera (= Amajoua or Amaioua saccifera, incorrectly cited as "Awiaiona") and Remigia physophora: "Rubiads afford a few instances of sac-bearing leaves, especially in the genus Amaiona (Aubl.). In caatingas of the Rio Negro, almost throughout its extent, grows Amaiona saccifera Mart., a small bushy tree with leaves three together, above a foot long, obovate with a minute apiculus, tapering to the base, where there are two contiguous sacs inhabited by small red wheeler: neotropical ant-plants and their ants 89 fire-ants. The fruit resembles a large plum (except that like the leaves it is harshly harry), and when ripe is soft and edible; but long before it reaches that stage the ants crowd on it and seem to suck the juices through the pores of the cuticle. To the same order belongs Remigia physophora Bth., a remarkable tree found at the falls of the Uaupes, having the aspect of an Amaiona, but the dry capsules and other characters of Cinchona and its allies. The opposite leaves, 9 inches long, are oblong-oval, obtuse with a short apiculus, near the base abruptly panduriform and bearing a small ant sac on the midrib. All the other known species of this large genus have non- sacciferous leaves." In 1889 Schumann also published on Duroia and Remijia. Of the former genus he studied the three species petiolaris, hirsuta and saccifcra, but his account is too long for quotation. In petiolaris and hirsuta the internodes of the terminal flower-bearing branches form hollow, spindle-shaped thickenings distally and these are provided with a longitudinal cleft or sometimes with two clefts, one above the other, in which the ants make their entrances. The third species, saccifera, has, as Spruce observed, a pair of sacs at the base of the leaf on the upper side. Each sac has its own preformed entrance, which is on the upper side of the leaf blade. Neither Schumann's figure nor his description yield a very clear notion of the position of these entrances. He also gives a brief account of Remijia physophora, which has similar sacs but their openings are on the lower surface of the leaf-base. Ule's description (1907) of D. hirsuta, which he observed in the field, is very clear. He writes: "To the family Rubiaceae belongs Duroia hirsuta K. Sch., a small dioecious tree, 3 to 5 meters high, which grows both in the inundated forest and on terra firma. The short-petioled leaves are about 18 to 24 Cm. long and 7 to 10 cm. broad and ovate. Above and along their edges they bear rather long, sparse, eventually deciduous hairs; beneath the ribs especially are always coarsely hairy. The stipules are united to form an elongate conical hood, covered basally with a circlet of long hairs, among which scattered glands persist. Duroia has terminal, corymbose cymes of white flowers. The terminal branches consist of an elongate internode, which is followed by a very short one and finally by the inflorescence. Now the elongate internode also develops towards its tip a bladder-like dilation which bursts open on the underside and there displays a groove the tips of which heal over. In this slit there is a perforation made by the ants. These hollow stems are always inhabited by two species of ants, Myrmelaehista nigella Roger and Azteca duroix Forel n. sp." The 90 bulletin: museum of comparative zoology formation of the internodal cleft by dehiscence, as described by Ule, is interesting in connection with the similar formation in Triplaris (see p. 49). More recently Bequaert (Wheeler and Bequaert, 1929, p. 16) has been able to study D. saccifcra in the type locality near Manaos, Brazil, where he found it growing in dense thickets of the second growth woods. He describes the plant and its domatia as follows: "It forms either a low bush about 6 feet high, with hard, woody twigs, or a small tree, 8 to 10 feet high, with an unbranched main stem of about 5 feet. The leaves are placed in whorls of three, more rarely opposite, especially in young plants, and near the base of the branches. They measure 15 to 30 cm. in length and 5.5 to 12 cm. in greatest width and are elongate-oval, with entire margins, ending in a short slender point. The basal half is gradually attenuate, the base itself briefly rounded off. The petiole is very short and almost wholly occupied by the lateral pouches. At the tips of the branches the leaves form an elongate bud enclosed in a large bract, which drops off after the leaves develop. The entire plant is covered with hispid, somewhat whitish hairs, which are particularly long on the stem, the midrib of the leaves and the myrmecodomatia. Neither flowers nor fruit were seen." Spruce's account of these has been quoted. "The myrme- codomatia of D. saccifera are two pouches at the base of the leaf on each side of the petiole. The sacs are completely separated from each other by the whole width of the petiole on the upper as well as on the under side of the leaf. They are nearly symmetrical, ovate, 10 to 14 mm. long, 6 to 7 mm. wide and 4 to 6 mm. thick, and are completely closed at the lower end and along the petiole, but open at the upper end by a narrow slit in the deep, sinuous notch that divides the base of the leaf- blade from the pouch. The pouches might be regarded as having been formed by the recurving of the decurent bases of the blade to the upper side of the leaf, and the growing fast of the free edges of the recurved portion of the petiole. If this conception of their mode of origin is correct, the outer surface of the domatia corresponds to the underside of the blade and their inner surface to the upperside. Both the inner and outer surfaces are densely covered with long, hispid hairs. Those of the inner surface converge towards the upper slit, which they partly close. The ants found in the myrmecodomatia were Solenopsis corti- calis Forel and Brachymyrmex heeri Forel var. aphidicola Forel. It is interesting to note that in spite of the pouches being inhabited by ants, the young leaves of this plant were badly damaged by leaf-cutting ants (Attini), while the older leaves were eaten by caterpillars. The same wheeler: neotropical ant-plants and their ants 91 species of Duroia was observed at Carmo, on the right bank of the Rio Braneo, September 1. In this locality the ants found in the pouches were Azteca ulei Forel var. cor dice Forel." The various ants which have been taken in the domatia of Duroia and Remijia are enumerated in the following list: (1) Solenopsis corticalis Forel. In leaf-sacs of Duroia saccifera. Amazonas (Bequaert). (2) Allomerus 10-articulatus Mayr. subsp. 8-articulatus. In leaf- sacs of Remijia physophora. Amazonas (E. Ule). (3) Allomerus 10-articulatus subsp. 7-articulatus Mayr. In leaf- sacs of D. saccifera Amazonas. (E. Ule). (4) Azteca angusticeps Emery. In internodes of D. petiolaris. Amazonas (K. Schumann). (5) Azteca depilis Emery. In internodes of D. hirsuta. Amazonas (K. Schumann). (6) Azteca duroice Forel. In internodes of D. hirsuta. Amazonas (E. Ule, A. Goeldi and J. Huber). (7) Azteca ulei Forel var. cordis Forel. In leaf-sacs of D. saccifera. Amazonas (Bequaert). (8) Myrmelachista (Decamera) nigella Roger. In internodes of D. hirsuta. Amazonas (E. Ule). (9) Myrmelachista (Decamera) schumanni Emery. In internodes of D. hirsuta. Colombia (K. Schumann). (10) Brachymyrmex heeri Forel var. aphidicola Forel. In leaf -sacs of D. saccifera. Amazonas (Bequaert). Owing to the small size of the domatia, especially the leaf-sacs, all of these ants belong to diminutive or very small species. Moreover, most of them are timid and harmless and none of them can be of any considerable use to the plants. So far as we are able to judge from the list, the ant fauna of the Duroias varies with the locality and consists largely of forms which occur also in Cordia nodosa and the Melastomacese, which have leaf-sacs (vide infra) much like D. saccifera and Remijia physophora, or in almost any convenient plant cavities. (B) Patima formicaria Johnston Mr. H. O. Lang, while on an expedition in British Guiana during 1922, discovered another Rubiaceous myrmecophyte with fistulose stems which are regularly inhabited by ants. He kindly sent me a number of herbarium specimens of the plant together with its tenants. Dr. I. M. Johnston of the Gray Herbarium has since described it as- 92 bulletin: museum of comparative zoology Patima formicaria (1924, p. 83), a species allied to P. guianensis Aublet, "but having taller tetragonal stems, larger long-acuminate leaves, larger flowers and apparently many-celled fruit." Mr. Lang has supplied the accompanying photographs (Plates 13-14) and the following field note: "The plant was growing in most cases as single stems like large-leaved shoots. Though this no doubt is its regular way, in a few instances there were as many as four or five together arising from the same root. They were about 6 to 9 feet high, with lemon-yellow flowers and spinach-green fruit. I found them growing in the tropical rain forest trees about 150 feet high and collected about 30 of these shoots from different places on the hill which is just at the mouth of the Merume Creek, facing the Mazaruni River. Although all the shoots of the plants were hollow, not all of them contained ants." The Gray Herbarium also possesses specimens of this plant collected by Hitchcock at Tumatumari on the Potaro River, B. G. The specimens received from Mr. Lang show that the plant is very smooth, with long, lanceolate, opposite leaves and tetragonal fistulose stems about 1.5 to 2 cm. in diameter. The longer internodes measure about 5 to 10 cm. and have large medullary cavities. Some of the shorter internodes are more swollen in the middle, or fusiform. There are elliptical openings made by the ants just below the nodes, and the insects gnaw through the latter, thus making the internodal cavities continuous. No Coccids were present on the walls of the cavities. The following ants were taken by Mr. Lang in the living internodes : (1) Neoponera carinulata Roger. (2) Pseudomyrma tenuis Mayr. (3) Crematog aster (Orthocrema) limata F. Sm. var. palans Forel. (4) Azteca traili Emery. (5) Camponotus (Paracolobopsis) patimoe Wheeler. (6) Camponotus (Paracolobopsis) patimoe var. dolentulus Wheeler. The first to fourth in this list are species that occur also in dead twigs of various neotropical plants. The Camponotus may have similar habits or it may, perhaps, prove to be an obligate tenant of the Patima. Borreria vcrticillata L. is yet another Rubiaceous plant in the stems of which I found a number of ants in British Guiana, but as only the dead stems are inhabited, this case had best be considered in connec- tion with a number of other nonmyrmecophytic plants, (see p. 92). wheeler: neotropical ant-plants and their ants 93 (C) Clerodendron Siphonanthus R. Br. No verbenaceous myrmecophytes have been recorded from the New World though there are several belonging to the genus Clero- dendron and at least one belonging to the genus Vitex in the Old World tropics. Mr. Zetek and I, while examining the ornamental trees and shrubs planted many years ago on the Prado at Balboa, C. Z., came upon a specimen of the Oriental Clerodendron Siphonanthus R. Br., which must have been set out as a seedling. Having attained a height of about seven feet, it was beginning to die as a result of heavy infesta- tion by scale insects. It had evidently flowered and fruited in pre- ceding years, because there were growing near it a number of vigorous young plants from a few inches to about three feet high. On closer examination the old plant was seen to be tenanted by two species of ants, Pseudomyrma gracilis var. hicolor and Azteca velox subsp. nigriventris. The former occupied only a single branch, the latter all the remaining branches and the trunk. The insects were living in the internodes, whose medullary cavities they had made continuous by gnawing through the nodes. In the smaller branches these cavities were as much as 4 to 5 mm., in the larger branches and trunk only 2.5 to 3 mm. in diameter. The ants had made no entrances in the walls, but seemed to have gained access to the medullary cavities through the broken ends of a few of the branches. At intervals on the walls of the internodal cavity there were latrines, i.e. blackened accumulations of faeces and infrabuccal pellets, invaded by many Nematodes, moulds and bacteria. Dr. Cobb has studied the Nema- todes. On the surfaces of the branches the ants were busily attending great numbers of Coccids, among which Mr. Zetek distinguished four species. The most abundant was identified by Dr. H. Morrison as Saissctia heemispherica Targ. Two species of Aleurodidse and two species of spiders were taken on the foliage. I have recorded this instance of an Oriental plant, belonging to a genus known to contain several myrmecophytes and peopled by Neotropical ants, because it is the converse of Morteo's case of the Triplaris amerieana introduced into the East Indies and there acquir- ing one of the native ants (Dolichoderus bituberculatus) as a tenant. I am inclined to believe that the Clerodendron sijjhonanthus at Balboa was first attacked by the scale-insects and that these then attracted the Aztecas and induced them to settle in the cavities of the stem and branches. The two cases, that of the Triplaris and that of the Clerodendron, suggest that some interesting modifications of ant- 94 bulletin: museum of comparative zoology behavior might be obtained by introducing Old World myrmecophytes into the American tropics and vice versa. Chapter 6. THE MYRMECOPHYTIC ACACIAS Several shrubs and trees of the huge Mimosaceous genus Acacia, which comprises more than 600 described species, widely distributed in the tropical and subtropical regions of both hemispheres, have unusually large, paired, stipular spines which are regularly inhabited by ants. These myrmecophytes may be divided into three groups, according to their peculiar discontinuous geographical distribution, the first comprising the famous bull-horn Acacias, ranging from Northern Mexico to Colombia, with a doubtful species in Cuba, the second represented by the single species, A. cavenia, in Paraguay, and the third comprising some seven species in the savannahs of Eastern Africa. The bull-horn Acacias present the most interesting and intricate problem and therefore require a more detailed dis- cussion; the Paraguayan and African forms, which are perhaps not true myrmecophytes may be dismissed with briefer discussion in the concluding paragraphs of this section. (A) The Bull-horn Acacias The bull-horn Acacias, known to the natives of Mexico as "cuer- nezuelo", "cornisuelo", "palin", or "guisache corteno" and to the Panamanians as "cuernito" or "caehito", are bushes or small trees, rarely attaining a height of 20 feet, with delicate pinnately compound leaves with one or more extrafloral nectaries on the upper surface of the petiole and usually one between each pair of pinnse on the rachis and with huge paired spines which are filled with a pulpy medullary substance till they are full-grown. The young leaflets produce small, elongate-elliptical, yellow or whitish food-bodies ("Beltian bodies") at their tips. The ants enter the mature spines by gnawing an opening just below the tip of one of the pair and then hollow both of them out, thus producing a bifurcate domatium with a single entrance. They collect, store and eat the food-bodies and visit the extra-floral nectaries. The flowers are yellow, buff or flesh- colored, small and aggregated in dense spadix-like, cylindrical spikes or globose heads. The pod-like fruits show considerable variation in structure in the different species, being indehiscent or dehiscent on one or both sides and with the seeds in some species embedded in a wheeler: neotropical ant-plants and their ants 95 sugary, pulp-like arillus. As a rule, the species prefer rather dry, open country (savannahs), but I have found one of the Panamanian forms (A. melanoceras) growing in swamps or moist jungle along water-courses. Until recently it was supposed that there were less than half a dozen authentic species of bull-horn Acacias, but Safford (1910, 1914, 1915, 1923) and Schenck (1913, 1914), after studying a considerable amount of herbarium material have recognized as many as 28. These are here listed alphabetically, with their known geographical distribution: buccrophora Robinson. British Honduras (Plate 15). bursaria Schenck. Western Guatemala (Plates 16-17). campccheana Schenck. Yucatan, Sinaloa (Plate 18). chiapensis Safford. Chiapas, Mexico. Collinsii Safford. Chiapas, Mexico (Plates 19-22). Cookii Safford. Eastern Guatemala (Plates 23-24). comigera Linne. (= spadicigera Schl. & Cham.) Vera Cruz, Mexico (Plates 25-29). costariccnsis Schenck. Costa Rica; Nicaragua (Plate 30). cubensis Schenck. Northern Cuba. dolichoccphala Safford. Veracruz, Mexico (Plate 31). donnelliana Safford. Honduras (Plates 32-33 a). furcella Safford. Veracruz, Mexico. globulifera Safford. Northern Yucatan (Plate 33 b.) Hernandezi Safford. Central Mexico. Hindsii Bentham. Salvador, Guatemala, Costa Rica, Southwestern Mexico (Plates 34-36). inter jecia Schenck. Singapore (in cultivation). -multi glandulosa Schenck. Eastern Panama (Plates 37-38). Nelsonii Safford. Guerrero, Southwestern Mexico (Plate 39). ■nicoycnsis Schenck. Costa Rica (Plate 40). panamensis Schenck. Panama. penonomensis Safford. Panama. rossiana Schenck. Veracruz, Mexico. sinaloensis Safford. Sinaloa, Mexico. sphaeroccphala Schlecht & Cham. Veracruz, Mexico (Plates 41-43). tepicana Safford. Tepic, Western Mexico. turgida Safford. Chiapas, Mexico (Plate 45). veracruzensis Schenck. Veracruz, Mexico. yueatanensis Schenck. Yucatan, Honduras. An even more recent study of these plants by Standley (1922, 1928) has led to a considerable reduction in the number of species. He re- 96 bulletin: museum of comparative zoology gards Hernandezi and furcella as synonyms of cornigera; sinaloensis and tcpicana as synonyms of Hindsii; chiapensis as a synonym of globulifera; yucatanensis of Collinsii; and penonomensis of costaricensis. Probably cubensis and inter jeeta are merely garden forms of cornigera. Schenck's multiglandulosa is certainly a synonym of melanoceras Beurling, which was overlooked by Schenck and Safford. With these changes the number of species in the foregoing list would be reduced to 20, and this number is probably too high. 1 Unfortunately Safford did not live to complete his study of the bull-horn Acacias. I have repro- duced photographs of these plants which he generously gave me several years ago. Among them is a photograph of a species with re- markably swollen and divergent spines, A. turgida, of which he seems to have published no description. We have as yet no knowledge of the precise species of bull-horn Acacia occurring in Colombia. Jacquinius recorded "A. cornigera" from Carthagena and Beurling (1854) long ago very briefly described an A. mclanoccroides taken by Billberg in the same locality 2 . Dr. George Salt informs me that a species grows at Bonda and Tacurina, and Forel described a subsp. gaigei of Pseudomyrma spinicola, a well known bull-horn ant as taken at Fundacion by Dr. G. M. Gaige. All these localities are in the dry Cienaga region of Northern Colombia. Probably the plant is A. costaricensis, the same species that occurs in the dryer parts of Panama and Costa Rica. Both Schenck and Safford have recognized several groups among the species of bull-horn Acacias. Safford establishes four groups, which are subdivided into sections. A fifth group, the Hebacantha?, contains several species not cited in the foregoing list, because their thorns are peculiarly flattened and not inhabited by ants. These plants are of peculiar interest as I shall endeavor to show in the sequel. The beginnings of our ecological knowledge of the bull-horn Acacias have been often recounted. The early botanists often referred to these plants, which were first observed and figured by Hernandez (1651) and Jacquinius (1763). Commelin figured the food-bodies as early as 1697 and Plukenet in 1720. All the other early accounts such as those of Breinius (1739) and Ph. Miiller (1752, 1768) and most of the later such as those of Beccari (1884-86), Schimper (1888) and Rettig (1904) are based either on herbarium material or on specimens grown in Euro- ■Such is also the opinion of Air. I. M. Johnston, who in a letter calling my attention to the identity of .4. yucatanensis and Collinsii, remarks: "I have investigated the other reductions in this group which Standley has made and am inclined to think that he can be followed in this particular instance with safety. I think that segregition in this group of plants has become too detailed and that the total number of species is'well under 20." 2 See footnote on p. 101, in connection with A. melanoceras. wheeler: neotropical ant-plants and their ants 97 pean botanical gardens. The type species, C. cornigera, was described by Linne in 1737 from material grown in George Clifford's garden. Safford (1923), from whom I take this fact, says that "it was after- wards found growing in its native habitat, near Laguna Verde in the mountains of Vera Cruz, Mexico in 1820 by the botanical explorer Christian Julius William Schiede and was described 10 year later under the name Acacia spadicigera, which must be regarded as a synonym of Linnaeus' Acacia cornigera". Hernandez's plant which, he says, was called "Hoitmamaxalli", or "forked thorn" by the Aztecs was recognized by Safford and described as a distinct species, A. hernandezi. F. Smith in 1862 published a note on ant-inhabited Acacia spines, which has been overlooked in the literature. He described the ant as "Pseudomyrma modesta". The specimens were collected by R. W. Stretch in Panama, the Acacia being in all probability A. costaricensis (= penonomensis Saff.), the ant one of the rufotestaceous forms of the species which have been more recently designated as Ps. belli Emery or Ps. spinicola Emery. The description is however too meager to admit of more precise identification. The first naturalist to make a careful study of the Acacias and their ants in the field was Thomas Belt (1874). His observations were on some of the plants growing about a league from Matagalpa, Nicaragua, and refer almost certainly to the species now known as Acacia costari- censis Schenck. As the locus classicus of our knowledge of the inter- relations of the plant and its ants and of the future hypothesis of myrmecophily, his account is worth quoting in extenso, especially as it contains certain statements that need correction or explanation: "Clambering down the rocks, we reached our horse and mule, and started off again, passing over dry weedy hills. One low tree, very characteristic of the dry savannahs, I have only incidentally mentioned before. 1 It is a species of acacia, belonging to the section Gummiferae, with bipinnate leaves, growing to a height of fifteen or twenty feet. The branches and trunk are covered with strong curved spines, set in pairs, from which it receives the name of the bull's-horn thorn, they having a very strong resemblance to the horns of that quadruped. These thorns are hollow, and are tenanted by ants, that make a small hole for their entrance and exit near one end of the thorn, and also burrow through the partition that separates the two thorns; so that the one entrance serves for both. Here they rear their young, and in !This reference is to p. 23, where he is describing the army-ant raids: "Many of the ajnaller birds build on the branches of the bull's-horn thorn, which is always thickly covered with small stinging honey-eating ants, that would not allow the Ecitons to ascend these trees 98 bulletin: museum of comparative zoology the wet season every one of the thorns is tenanted; and hundreds of ants are to be seen running about, especially over the young leaves. If one of these be touched, or a branch shaken, the little ants (Pseudo- myrma bicolor, Guer.) swarm out from the hollow thorns, and attack the aggressor with jaws and sting. They sting severely, raising a little white lump that does not disappear in less than twenty-four hours. "These ants form a most efficient standing army for the plant, which prevents not only the mammalia from browsing on the leaves, but delivers it from the attacks of a much more dangerous enemy — the leaf -cutting ants. For these services the ants are- not only securely housed by the plant, but are provided with a bountiful supply of food, and to secure their attendance at the right time and place, the food is so arranged and distributed as to effect that object with wonderful perfection. The leaves are bipinnate. At the base of each pair of leaflets, on the mid-rib, is a crater-formed gland, which, when the leaves are young, secretes a honey-like liquid. Of this the ants are very fond; and they are constantly running about from one gland to another to sip up the honey as it is secreted. But this is not all; there is a still more wonderful provision of more solid food. At the end of each of the small divisions of the compound leaflet there is, when the leaf first unfolds, a little yellow fruit-like body united by a point at the base to the end of the pinnule. Examined through a microscope, this little appendage looks like a golden pear. When the leaf unfolds, the little pears are not quite ripe, and the ants are continually employed going from one to another, examining them. When an ant finds one sufficiently advanced, it bites the small point of attachment; then bending down the fruit-like body, it breaks it off and bears it away in triumph to the nest. All the fruit-like bodies do not ripen at once, but successively, so that the ants are kept about the young leaf for sometime after it unfolds. Thus the young leaf is always guarded by the ants ; and no caterpillar or larger animal could attempt to injure them without being attacked by the little warriors. The fruit-like bodies are about one-twelfth of an inch long, and are about one-third of the size of the ants; so that an ant carrying one away is as heavily laden as a man bearing a large bunch of bananas. I think these facts show that the ants are really kept by the Acacia as a standing army, to protect its leaves from the attacks of herbivorous mammals and insects. "The bull's-horn thorn does not grow at the mines in the forest, nor are the small ants attending on them found there. They seem specially adapted for the tree, and I have seen them nowhere else. wheeler: neotropical ant-plants and their ants 99 Besides the Pseudomyrma, I found another ant that lives on these acacias; it is a small black species of Crematogaster, whose habits appear to be rather different from those of Pseudomyrma. It makes the holes of entrance to the thorns near the center of one of each pair, and not near the end, like the Pseudomyrma; and it is not so active as that species. It is also rather scarce; but when it does occur, it occupies the whole tree, to the exclusion of the other. The glands on the acacia are also frequented by a small species of wasp {Polybia occidentalis) . I sowed the seeds of the acacia in my garden, and reared some young plants. Ants of many kinds were numerous; but none of them took to the thorns for shelter, nor the glands and fruit-bodies for food; for, as I have already mentioned, the species that attend on the thorns are not found in the forest. The leaf- cutting ants attacked the young plants, and defoliated them, but I have never seen any of the trees out on the savannahs that are guarded by the Pseudomyrma touched by them, and have no doubt the acacia is protected from them by its little warriors. The thorns, when they are first developed, are soft, and filled with a sweetish, pulpy substance; so that the ant, when it makes an entrance into them, finds its new house full of food. It hollows this out, leaving only the hardened shell of the thorn. Strange to say, this treatment seems to favor the development of the thorn, as it increases in size, bulging out towards the base; whilst in my plants that were not touched by the ants, the thorns turned yellow and dried up into dead but persistent prickles. I am not sure, however, that this may not have been due to the habitat of the plant not suiting it. "These ants seem at first sight to lead the happiest of existences. Protected by their stings, they fear no foe. Habitations full of food are provided for them to commence housekeeping with, and cups of nectar and luscious fruits await them every day. But there is a reverse to the picture. In the dry season of the plains, the acacias cease to grow. No young leaves are produced, and the old glands do not secrete honey. Then want and hunger overtake the ants that have revelled in luxury all the wet season; many of the thorns are depopulated, and only a few ants live through the season of scarcity. As soon, however, as the first rains set in, the trees throw out numerous vigorous shoots, and the ants multiply again with astonishing rapidity." The ant mentioned in this description is almost certainly mis- identified. Pseudomyrma bicolor does occasionally nest in Acacia spines but it can hardly be described as a "small" ant, its colonies 100 bulletin: museum of comparative zoology are not very populous and it does not attack and sting unless the spines are roughly seized. Belt, I feel confident, actually observed some form of Ps. belti or spinicola. Since the appearance of his book, several observers have published accounts on the Acacias or their ants, notably Francis Darwin (1877), Beecari (1884-86), Delpino (1886-89), Schimper (1888), Emery (1892), Wheeler (1912), Wasmann (1915), Schwarz (1917), Calvert (1917), Safford (1923), Menozzi (1927). C. F. Baker, J. Bequaert, P. P. Calvert, A. Dampf, J. Zetek and others have furnished me with valuable specimens and data collected in Costa Rica, Honduras, Panama and Mexico. My own earlier observations (1913) need not be introduced in this connection, but I shall later return to some of them. Attention may here be called to the fact that my identification of Acacia sphaerocephala and cornigera seems doubtful in the light of the more recent taxonomic revisions of Schenck, Safford and Standley. The same is true of the specific identifications of Acacias by most of the other authors cited above. Thus Menozzi figures the spines of two species of Acacia as belonging to A. spadicigera (that is cornuta), but they are clearly those of A. costaricensis and Hindsii. During 1923 and 1924 I had an opportunity to study two of the three known Panamanian Acacias, namely A. costaricensis (= peno- nomensis according to Standley) and A. melanoceras and therefore transcribe some of my field notes which I made on the general char- acters of these plants. The former species I found only on the dryer Pacific side of the Isthmus, in the vicinity of Las Sabanas, near Panama City and less frequently near Red Tank in the Canal Zone. It is probably more abundant in the savannah region further eastward. It is a rather coarse, sturdy bush, rarely more than five or six feet in height and often growing along trails or roadsides through the second growth jungle or in clearings. The grayish green leaves have rather few pairs of pinnae (about 8), with a row of three nectaries on the petiole and one at the junction of each pair of pinnae on the rhachis. The spines are terete and moderately long and diverging, green at first, then reddish or chocolate brown. They seem to become hollow rather early, owing to drying up of their pulp-like pith. The flowers are in elongate spikes, the fruit turgid and when ripe splitting along both sides. The young leaflets bear yellow Beltian bodies, which the ants were seen to carry into the spines, while others were feeding at the foliar nectaries. Quite a number of the plants were examined and their ant and other inhabitants noted and collected. I select the following observations as the most interesting: wheeler: neotropical ant-plants and their ants 101 April 2, 1923. Observed numerous Acacias, from a foot to five feet high, along the Tumba Muerta Road, near Las Sabanas. Nearly all of them were inhabited by Ps. spinicola subsp. atrox. The spines of two plants, however, contained only Ps. gracilis, except a single pair on one of them which was tenanted by a colony of Brachymyrmex heeri var. obscurior and a few dead spines on the other which were inhabited by Camponotus (Myrmobrachys) brevis. The gracilis colonies were very flourishing, with much brood and numerous winged sexual forms. The workers had stored quantities of Beltian bodies in the spines, and these also contained a few Coccids and several empty Microdon puparia (vide infra). July 2, 1924. Near Punta Paitea. Thirty Acacias growing along the trails near the military camp varied from a foot to 6 ft. in height. The thorns of 24 of them were inhabited exclusively by Ps. atrox, and one had no ant-inhabitants though it was quite as flourishing as the other specimens. In two bushes, only a foot high, evidently young suckers growing from the roots of a felled bush, I found the spines inhabited by isolated dealated females with brood, but without any workers, though pupse of the latter were sometimes present. In one case the leaves of a large bush inhabited by atrox were much gnawed (by Chrysomelids). Five of the bushes were tenanted by Ps. gracilis exclusively. Owing to its timid disposition, this ant cannot be said to afford much protection to the plants. Ps. atrox, however, stings severely, but it does not attack unless the foliage is roughly handled. A. melanoceras Beurling (1854, p. 123) is clearly the same as the species described as A. multiglandulosa by Schenck (1913) and based on material in the Berlin Herbarium collected in 1825 by J. G. Billberg in the vicinity of Porto Bello, Panama. This is evidently part of the material on which Beurling founded his species. 1 Safford has figured and redescribed the species from specimens taken by Pittier at the head of the Gatun Valley, Panama. I include a brief description of il find that Standley (1928) has reached the same conclusion in regard to the identity of this plant. The following is a transcript of Beurling's original description. Acacia melanoceras n. sp. {Acacia sphaeracephala Cham, et Schlect. var. sec. Bentham in herbar. Reg. Acad, scient. holm.); glabra, (ex siccatione?) nigrescens, ramis teretiuscuhs, verruculis; aculeis stipularibus binis, in cornua basi connata divaricata recte inftata nigricantia nitida demum excrescentibus; petiolis pinnatis, ultra 20-jugis, infra jugum infimum supra excavata — foveolatis (fovea glanduhs minutis confertis cupuliformibus repleta); foliolis circiter 20 jugis, oblongo-lineanbus sub- falcatis. 2-3 lin. longis, H lin. latis, apice (sub lente) minutissime denticulatis; flonbus in capitula globosa congestis; capitulis pedicellatis (pedicellis 3-4-nis), in racemos elongatos laterales terminalesque saepe geminates (unum longiorem alterum breviorem) dispositis, No. 289. Mimosa comigera (Billberg) (Porto Bello) In silvis ad viani versus Panama. In a toot-note Beurling adds: "Prope Sanct. Lazaro Carthagense a Billbergio lecta est species simiUima: "No 139. Mi7noso comigera (Billb.), "vix nisi colore hand nigrescente. pnmarum jugis paucionbus foliolisque duplo longioribus latioribus rectis diversa. (Acadia melanoceroides Beul. mnscnpt). 102 bulletin: museum of comparative zoology the living plant, which is much more beautiful than A. costaricensis or indeed than any of the other species I have seen growing in Central America and would be a more ornamental plant under cultivation than A. cornigera which is occasionally grown in tropical botanical gardens. I have encountered A. melanoceras which, according to Standley, "is a common shrub in the swamps and forests of the Atlantic slope," on only two occasions, once near the head-waters of the Rio Agua Salud (March 6, 1923), and once at Marajal near Colon (July 26, 1924). Both of these localities are on the moist Atlantic side of the Isthmus. On the Rio Agua Salud there were only a few bushes, each about 12 ft. high, growing on the bank of the stream very near the water; at Marajal there were several fine trees, some of which were 18 or 20 feet high, with graceful, smooth, gray-barked trunks, upright and usually growing in a cluster from the same root (Plate 37 a). The leaves are large and moss-green and have many more pinnae than penonomensis. A count of 50 of them showed the number to vary from 12 to 25 pairs, with an average of 20 to 22. The young leaflets bear at their tips rather large, golden- yellow Beltian bodies. The upper surface of the petiole bears num- erous (20-30) conical nectaries, and there is a single nectary on the rhaehis between each pair of pinna?. The spines are long (2 to 23^ inches), straight and diverging, smooth and terete, gradually tapering to a short, very acute point. When young they are green, then turn to a brilliant crimson and finally become rich chestnut brown. They are inhabited by a black Pseudomyrma, satanica, which is larger and even more vicious than spinicola. I have not seen the flowers, but the trees at Marajal were bearing clusters of mature green pods, which were straight, cylindrical, with a short terminal snout and measured 3 to 4 inches in length. The pedicel measured about three- quarters of an inch. The pod contained a firm, white, sweetish and edible pulp enveloping a row of black seeds. According to Beurling, Safford and Standley, the flowers are in globose heads. Safford describes them as 7 mm. long, 6 mm. in diameter, solitary or in pairs, borne in the axils of the bracts on long erect branchlets composed of many nodes. Dr. J. Bequaert has recently been able to make some observations on A. Collinsii (= yucatanensis Schenck) and its ants in Honduras. Since little has been written on this Acacia I reproduce the notes which he sent me: "The ant acacia of northern Honduras (Acacia Collinsii Schenck) usually forms an erect bush, 6 to 15 feet high, with a main trunk 1 to 3 wheeler: neotropical ant-plants and their ants 103 inches in diameter and covered with many slender, short side branches. The size and shape of the spines vary considerably on the same bush, those of the main trunk, at the foot of the branches, being much longer and twisted in horn-fashion. Young spines are either green or bright red and both types occur on the same bush. They soon become naturally hollow, without the help of the ants, which merely cut the opening below the tip and remove the dried pith. "These acacias are particularly abundant near the coast, a short distance (one or two miles) from the shore, beyond the lagoons and mangrove swamps. They grow in dry, sandy, slightly undulating areas which appear to be ancient, fixed sand dunes and are covered with short grass and scattering shrubs and low trees. Many specimens may be seen along the main line of the Trujillo Railroad, about 15 to 25 kilo- meters from Puerto Castilla (near the stops known as Los Cuartos and El Canal). Only two small specimens were seen at Puerto Castilla, on the sandy levee between the sea and the mangrove swamp. At El Canal a number of them were also found in a rather dense and more humid wooded gallery along the banks of a stream. These specimens were larger and more tree-like than usual, reaching 20 to 25 feet in height, widely branched at the top, but with the main trunk, 4 to 5 inches thick, almost free of side branches, although covered with heavy and strongly twisted spines. Further inland I only observed the plant on one occasion, namely a single, bush-like individual which grew on the high, sandy, and densely wooded bank of the Rio Aguan, near Prieta, about 90 kilometers from Puerto Castilla along the railroad to Olanchita. "The black ant (Pseudomyrma bclti) I found only in two plants, which grew near the sea shore at Puerto Castilla. The brownish form (Ps. bclti subsp. bequaerii) is the common inhabitant of all the acacias near Los Cuartos and El Canal, where it occurs as well in the bushy plants of the dry, open areas as in the more tree-like form of the forest gallery. The subsp. bequaerii was also found in the single bush near Prieta. I observed how these ants actively collect the Beltian bodies at the tips of the leaflets and also visit the nectary near the foot of the petiole. At the time of my observations (March), most of the plants had flower buds, but only very few were actually blooming. After much search two or three seed-pods could still be obtained. Many of the bushes had very small, young leaves, just emerged from the bud, with food-bodies still attached. These food-bodies were either yellowish white or more rarely blackish. Both forms of Pseudomyrma are very aggressive; their sting is painful, but the pain soon abates." 104 bulletin: museum of comparative zoology The following list comprises the various ants recorded as living in the spines or on the foliage of the bull-horn Acacias: (1) Pseudomyrma belti Emery. In spines of Acacia sp. (probably costaricensis). Costa Rica (A. Alfaro; P. P. Calvert). In thorns of A. Collinsii; Honduras (J. Bequaert). (2) Pseudomyrma belti subsp. bequaerti Wheeler. In spines of A. Collinsii. Honduras (J. Bequaert). (3) Pseudomyrma belti subsp. fellosa Wheeler. In spines of A. cos taricensis. Nicaragua (C. F. Baker; W. Fluck). (4) Pseudomyrma belti subsp. fulvescens Emery. In spines of A. Hindsii and Acacia sp. Guatemala (Wheeler); Acacia sp. Guatemala (Schwarz and Barber); British Honduras (J. D. Johnston; C. F. Baker); Mexico (E. Palmer, D. L. Crawford, Jourdain, A. Petrunke- vitch, F. Knab); In spines of A. sphaerocephala., Mexico (Rangel, G. N. Collins, L. G. Culvas, J. M. Cuaron); A. Collinsi, Mexico (G. N. Collins) ; A. cornigera Mexico (G. N. Collins) ; A. Hindsii Mexico (G. N Collins). (5) Pseudomyrma belti subsp. obnubila Menozzi. In spines of A. "spadicigera" (probably costaricensis or Hindsii) Costa Rica (H. Schmidt). (6) Pseudomyrma belti subsp. saffordi Wheeler. In spines of A. Colli?isi. Mexico. (G. N. Collins). Acacia sp. Guatemala (Wheeler). (7) Pseudomyrma belti subsp. venefica Wheeler. In spines of A. Hindsii. Mexico (J. H. Batty, C. H. T. Townsend); Acacia sp. Mexico (C. F. Baker). (8) Pseudomyrma belti subsp. vesana Wheeler. In spines of Acacia sp. Mexico (F. Knab). (9) Pseudomyrma belti subsp. wasmanni Wheeler. In spines of A. sphaerocephala (W. Brakmann). (10) Pseudomyrma brunnea F. Smith. In spines of A. "spadicigera" (probably costaricensis or Hindsii) Costa Rica (H. Schmitt). (11) Pseudomyrma flavididaF. Smith. In spines of A. "spadicigera" (probably costaricensis or Hindsii). Costa Rica (H. Schmitt). (12) Pseudomyrma gracilis Fabr. In spines of A. Hindsii and Acacia sp. Guatemala (Wheeler); A. costaricensis. Panama (Wheeler) A. sphaerocephala. Mexico (Schenck). (13) Pseudomyrma gracilis subsp. bicolor Guer. In spines of A. costaricensis, Panama (Wheeler). (14) Pseud&myrma gracilis subsp. mexicana Roger. In spines of Acacia sp. Costa Rica (A. Alfaro). wheeler: neotropical ant-plants and their ants 105 (15) Pseudomyrma kuenckeli Emery. In spines of Acacia sp. Costa Rica (A. Alfaro); A. "spadicigera" (probably costaricensis or Hindsii) Costa Rica (H. Schmitt). (16) Pseudomyrma nigrocincta Emery. In spines of Acacia sp. Costa Rica (A. Alfaro; P. P. Calvert). (17) Pseudomyrma nigropilosa Emery. In spines of Acacia sp. Costa Rica (A. Alfaro; P. P. Calvert). (18) Pseudomyrma peltata Menozzi. In spines of A. "spadicigera" (probably costaricensis or Hindsii) Costa Rica (H. Schmitt). (19) Pseudomyrma satanica Wheeler. In spines of A. melanoceras. Panama (Wheeler). (20) Pseudomyrma sericea Mayr. var. acaciarum Wheeler. In spines of A. costaricensis. Panama (Wheeler). (21) Pseudomyrma spinicola Emery. In spines of Acacia sp. Costa Rica (A. Alfaro; P. Biolley). (22) Pseudomyrma spinicola subsp. atrox Forel. In spines of A. costaricensis. Panama (E. D. Christophersen ; Wheeler). (23) Pseudomyrma spinicola subsp. modcsta F. Sm. In spines of Acacia costaricensis. Panama (R. W. Stretch). (24) Pseudomyrma spinicola subsp. convarians Forel. In spines of Acacia sp. Guatemala (Peper). (25) Pseudomyrma spinicola subsp. gaigei Forel. In Acacia spines (very probably), Colombia (F. M. Gaige). (26) Pseudomyrma spinicola subsp. infernalis Wheeler. In spines of A. costaricensis. Panama (Wheeler). (27) Pseudomyrma spinicola subsp. scelerosa Wheeler. In spines of A. costaricensis. Nicaragua (C. F. Baker). (28) Pseudomyrma subtil issi ma Emery. In spines of Acacia sp. Costa Rica (A. Alfaro). (29) Solenopsis zeteki Wheeler. Nesting in dead twig caught among spines on trunk of A. melanoceras. Panama (Wheeler). (30) Solenopsis sp. Nesting in flower peduncles of Acacia sp. Guate- mala (Wheeler). (31) Crematogaster acuta Fabr. Running on foliage of A. costari- censis. Panama (Wheeler). (32) Crematogaster (Orthocrema) atra Mayr. In spines of A. vera- cruzensis. Mexico (A. Dampf). (33) Crematogaster (Orthocrema) brevispinosa Mayr. In spines of Acacia sp. Costa Rica (A. Alfaro). A. costaricensis. Nicaragua (E. Chamorro); A. veracruzensis . Mexico (Schenck). (34) Crematogaster {Orthocrema) brevispinosa var. minutior Forel. 106 bulletin: museum of comparative zoology Nesting in accumulations of carton around spines of A. cornigera in botanical garden, Port of Spain, Trinidad (Wheeler). (35) Crematogaster {Orthocrema) brevispinosa subsp. timulifera Forel. In spines of A. Hindsii. Guatemala (Wheeler). (36) Crematogaster {Orthocrema) corvina Mayr. In spines of A. vera- cruzensis. Mexico (A. Dampf). (37) Crematogaster {Orthocrema) curvispinosa Mayr var. panamana Wheeler. In spines of A. costaricensis. Panama (Wheeler). (38) Leptothorax {Goniothorax) echinatinodis Forel subsp. cordincola Wheeler. In spines of A. costaricensis . Panama (Wheeler). (39) Leptothorax {Goniothorax) echi?iatinodis subsp. schmidti Me- nozzi. In spines of A. "spadicigera" (probably costaricensis or Hind- sii). Costa Rica (H. Schmidt). (40) Cryptocerus {Paracryptocerus) minutus Fabr. In spines of A. costaricensis. Panama (Wheeler); A. "spadicigera" (probably costa- rie7isis or Hindsii). Costa Rica (H. Schmidt). (41) Cryptocerus {Cyathoccphalus) pallcns Klug. In spines of A. Collinsi. Mexico (G. N. Collins). (42) Cryptocerus {Cyathoccphalus) pollens var. discocephalus F. Smith. In spines of Acacia sp. Costa Rica (A. Alfaro). (43) Dolichoderus {Hypoclinea) championi Forel var. In spines of A. Hindsii. Guatemala (Wheeler). (44) Dolichoderus {Hypoclinea) diversus Emery var. ficosus n. v. In spines of A. cornigera. Mexico (G. N. Collins). (45) Azteca velox Forel. In spines of A. Hindsii. Guatemala (Wheeler). (46) Brachymyrmex hecri Forel var. obscurior Forel. In spines of A. costaricensis. Panama (Wheeler). (47) Camponotus {Myrmobrachys) planatus Roger var. acacice Emery. In spines of A. Hindsii. Guatemala (Wheeler); Acacia sp. Costa Rica (A. Alfaro); A. "spadicigera" (probably costaricensis or Hindsii). Costa Rica (H. Schmidt). (48) Camponotus {Myrmobrachys) brevis Forel. In spines of A. cos- taricensis. Panama (Wheeler). (49) Camponotus {Myrmobrachys) striatus F. Smith. In spines of Acacia sp. Costa Rica (A. Alfaro); A. costaricensis. Panama (Wheeler). (50) Camponotus {Myrmocladoecus) mucronatus Emery subsp. sants- chii Forel. In spines of A. Hindsii. Guatemala (Wheeler). (51) Camponotus {Myrmocladoecus) rectangularis Emery. In spines of Acacia sp. Costa Rica (A. Alfaro). (52) Camponotus {Colobopsis) sp. In spines of Acacia sp. Costa Rica (A. Alfaro). wheeler: neotropical ant-plants and their ants 107 (53) Paratrechina (Nylanderia) longicornis Latr. Running on Acacia sp. Costa Rica (A. Alfaro). 1 Of the various ants listed only three species can be regarded as obligate or definitely associated with the bull-horn Acacias, namely Ps. belti, spinicola and satanica; all the others are species or sub-species and varieties of species which more frequently nest in dead twigs of a great number of different plants. Emery did, indeed, describe Ps. belti from specimens taken from Cordia alliodora domatia, but this must have been a very exceptional occurrence, or more probably due to an erroneous label. Two of the forms listed, Ps. gracilis and Camponotus planatus var. acacia, are of special interest. The former, though a very frequent tenant of dead twigs and Cordia domatia in regions where there are no Acacias, nevertheless exhibits a strong proclivity not only to inhabit the spines of these plants, wherever they are available, but also to perforate them at the same point, to visit the foliar nectaries and to collect the food-bodies. In other words, this ant has acquired all the peculiarities of behavior of the three obligate Acacia tenants, Ps. belti, spinicola and satanica. This is perhaps true also of some or all of the other Pseudomyrmas in the list. In my previous paper (1913) I de- scribed the founding of gracilis colonies in the thorns of young Acacias at Quirigua, Guatemala. In that region I found a locality in the banana plantations where gracilis was the only ant inhabiting the Acacias. As previously stated, it is also not infrequently the sole tenant of A. cos- taricensis in Panama. Of course, it is quite possible that the gracilis associated with Acacias represents a distinct physiological race derived and as yet morphologically indistinguishable from the form occurring more generally in dead twigs. At any rate, the case is interesting be- cause it shows such a perfect adaptation to the bull-horn Acacias by particular colonies of a species which as a rule exhibits no adaptations to ant plants beyond those exhibited by most other species of Pseu- domyrma. Camponotus planatus var. acaci&, as Alfaro (Emery, 1S92) and I (1913) have found, frequently inhabits the same Acacias as Ps. belti and gracilis in Costa Rica and Guatemala. I described the mutual rela- tions of these ants as follows: "That the Camponotus does not, as Emery supposed, merely take possession of thorns excavated and abandoned by the Pseudomyrma, was proved on one occasion when I 'Schenck (1914) records Pseudomyrma arboris-sancto? as occurring in the spines of A. sphaerocephala, spadicigera and veracruzensis in Mexico. The validity of this identification, which was made by Reichensperger, may be seriously doubted. In all probability the specimens belonged to some reddish subspecies of Ps. belti or spinicola. 108 bulletin: museum of comparative zoology found a small group of Camponotus workers busily engaged in per- forating a green thorn. It is probable, therefore, that the Camponotus queens, after their nuptial flight, seek out the acacias and enter their young thorns even when the trees are already inhabited by the Pseudomyrma, and that the Camponotus workers continue this work side by side with the Pseudomyrmas, both species competing for and taking possession of the thorns as fast as they attain the proper size and maturity. It is certainly extraordinary that C. planatus, which throughout tropical America so constantly lives in hollow twigs, should be able in widely separated localities to utilize the acacia thorns as perfectly and in precisely the same manner as the regular Pseudo- myrmas. That the Camponotus is, if anything, even more adroit in its use of the extrafloral nectaries becomes apparent when one follows the ant as it moves over the leaves, for it begins with the nectary at the base of the petiole and carefully visits each in turn, whereas the foraging Pseudomyrmas are much more desultory and less business- like. I have not seen the Camponotus collecting the Beltian bodies, but I doubt not that they make quite as good use of them as of the nectar. The behavior of the two species of ants towards each other is peculiar. They seem never to quarrel, and if not too close together, pass one another on the twigs and leaves with an air of complete indifference. But when two of them happen to meet squarely face to face, each starts back suddenly and, curiously enough, the Pseudo- myrma always recoils more vigorously than the Camponotus. There is something ludicrous in this behaviour because both ants are of about the same bulk, and the Pseudomyrma is really the more powerful and possesses a formidable sting, whereas the Camponotus is much less pugnacious and can defend itself only with its rather feeble mandibles and formic acid battery. But it smells rather strongly of formic acid, and I believe that this produces the more decided reaction on the part of the Pseudomyrma." I regarded the mutual relations of the Camponotus and Pseu- domyrma as a case of parabiosis, but Wasmann (1915, p. 128) has objected to my use of this word, because the two species of ants do not inhabit different parts of the same nest as in the case of Crematogaster parabiotica and Dolichodcrus (Hypoclinea) parabioticus, to which Forel first applied the term, "but different nests (spines) on the same tree or branch." I believe, however, that all the pairs of spines that are converted into domatia on an Acacia may be really regarded as so many chambers of a single nest, when the ant-colony is well-developed. It is only the incipient colony that is confined to a single pair of spines. wheeler: neotropical ant-plants and their ants 109 One might, of course, invent some other term for the relations of mutual tolerance exhibited by the Camponotus and Pseudomyrma, but this seems hardly necessary. It remains to be seen whether the concept of parabiosis may be extended to include all the other cases in which two or more species of ants inhabit the domatia of the same plant (Acacia, Cordia, Triplaris, Cecropia, etc.) Besides the ants enumerated above the various Acacias also harbor a considerable number of miscellaneous insects and other organisms, which are briefly noticed in the following list: (1) Aves. Birds, probably of several species, not infrequently build their nests in Acacia bushes or trees inhabited by the stinging Pseu- domyrmas. This was observed by Belt in Nicaragua (A. costaricensis) and by myself both in Guatemala (A. Hindsii) and Panama {A. costaricensis). Hymcnoptera. Dr. E. A. Schwarz (1917) bred several species parasitic on beetle larva 3 from an Acacia trunk from Tampico, Mexico, but has cited none of them by name. I have noticed most of the following forms : (2) Chalcidids. Bred from spider's eggs attached to twigs of A. costaricensis. Panama (Wheeler). (3) Braconids. Swept from foliage of A. costaricensis. Panama (Wheeler). (4) Solitary wasp. Nest made in an old thorn of .4. costaricensis. Panama (Wheeler). (5) Polybia sp. Nests constructed on branches of A. Hindsii in Guatemala (Wheeler). (6) Polybia sp. Nest on A. costaricensis, Panama (J. Zetek). (7) Polybia occidentalis. Cited by Belt as visiting the foliar nec- taries of Acacia (costaricensis) in Nicaragua. (8) Halictns sp. A small bee visiting the flowers of A. Hindsii in Guatemala (Wheeler). (9) Trigona sp. A black stingless bee visiting the flowers of A. costaricensis, Panama (Wheeler). Lepidoptera. The caterpillars of several species of moths feed on various parts of the Acacias notwithstanding the presence of the stinging Pseudomyrmas : (10) Adelocephala xanthochroia Schauss. According to Carlos Hoffmann (teste A. Dampf) the caterpillars of this moth feed on the pulp of the seed-pods of Acacias at Misanhtla, Vera Cruz. (11) Small moth caterpillars, which devour the foliage and leaflets and attach their cocoons to the twigs of A. costaricensis at Punta 110 bulletin: museum of comparative zoology Paitea, Panama. Several of them were observed on single plants inhabited by Pseudomyrma atrox. (12) A second small moth caterpillar was found cocooning on the stem of A. costaricensis. (13) A third was living in old spines of the same species of Acacia. (14) A Psychid larva had its case attached to a twig of the same plant. Diptera. I have observed the larva? or pupae of five species of this order, without being able to secure the adults: (15) In some localities in Guatemala (Esquintla, Patulul) the upper surfaces of the leaflets of A. "cor'nigera" bore beautiful little spherical galls, 5 to 6 mm. in diameter, single or in clusters and resembling minute strawberries, as they were bright red and uniformly covered with papillae (Plate 46 a). Each of these galls contained a Dipteron (Cecidomyid) larva and had a preformed rhaphe along which it dehisces when brown and mature, and permits the adult fly to escape. Pseudomyrma fuhescens is very fond of visiting these galls when young and succulent, and was often seen gnawing away the covering of papillae, but not eating in far enough to injure the enclosed larva. (16) A second gall of much larger size and woody texture was occasionally found on the flower-stems of A. Hindsii in Guatemala, but as I could secure only old and dried specimens, I am unable to make any statement in regard to the insect. (17) A very peculiar compound woody gall (Plate 46 b) was frequently found on the twigs and especially between and around the spines of A. costaricensis near Panama City. It consists of a number of tubular structures, each with an opening at its summit and containing in its more enlarged basal portion a Cecidomyid larva which I did not succeed in rearing. (18) Several of the thorns of A. costaricensis at Las Labanas, Panama and Red Tank, C. Z., inhabited by Ps. gracilis, contained empty, rather smooth, brown puparia (about 7 mm. long and 3 mm. broad) of a small Microdon sp. Since the openings of the thorns were only large enough to permit the slender ants to pass in or out I am unable to account for the egress of the fly after its emergence. The flies had evidently emerged normally since the anterior dorsal portion of the puparia had been broken open at the usual transverse suture. Perhaps the insects had been devoured by the ants. From the fact, however, that these puparia were encountered in more than a dozen pairs of spines on different bushes in two localities, we must infer, I be- lieve, that the Microdon is a regular syncekete in the nests of Ps. gracilis. wheeler: neotropical ant-plants and their ants 111 (19) Among some spider's eggs in a cocoon attached to the twigs of A. costaricensis I found a Muscid puparium, probably that of a Tachinid. Coleoptera. Several beetles have been recorded from Acacias, but only one has been specifically identified: (20) Agrilus sp. A small bronze-green species was common on the foliage of .4. costaricensis at Punta Paitea, Panama. Several pairs were taken in copula. (21) Agrilus sp. A larger bronze-green form, not uncommon on the same plant in the same locality. (22) Agrilus sp. Bred by Dr. E. A. Schwarz (1917) from the trunk of Acacia sp. from Tampico. (23-29) Dr. Schwarz also bred seven species of Cerambycidse (one Cerambycine and six Lamiids) from the same trunk. (30-31) At Las Sabanas, Panama two unidentified species of Chrysomelidse were found on the foliage of A. costaricensis. The in- jury to the foliage, occasionally noticed, probably results from the attacks of these or allied species. (32) Curculionid. The larva, apparently of some weevil, was found living in the spines of A. costaricensis near Las Labanas, Panama, and feeding on the pith. (33) Curculionid sp. A small black species taken on the foliage of the same Acacia. (34) Bruchus cincrifer Fabr. Cited by Schenck (1914) as boring into the pods and feeding on the seeds of A. sphaerocephala in the Mexican tierra caliente. (35) Bruchus sp. Possibly the same as the preceding observed by Carlos Hoffmann (teste A. Dampf) as occurring in the seeds of Acacia sp. at Misanthla, Vera Cruz. Through the holes made by this beetle the caterpillars of Adelocephala xanthochroia enter the pods and feed on the pulp. (36) Bruchus sp. Dr. Schwarz observed this species, which may be the same as B. cinerifer, infesting the flowers of an Acacia sp. at Tampico and ovipositing and developing in its pods "without being molested by the ants in any of its stages." (37) Bothrideres sp. A Colydiid bred by Dr. Schwarz from the trunk of Acacia sp. from Tampico. (38) Lathropus sp. A Cucujid from the same trunk. (39) Trogosita sp. An Ostomid from the same trunk. (40) Clerus sp. Bred from the same trunk by Dr. Schwarz. Orthoptera (41) Blattid sp. A large compressed ootheca of some 112 bulletin: museum of comparative zoology roach was taken from the cavity of a large dead spine of A. melan- oceras at Marajal, C. Z. (Wheeler). Isoptera. (42) Eutermes sp. An ellipsoidal nest of this termite was situated among the branches of an A. melanoceras tree at Marajal and had galleries descending from it along the trunk. When the latter were broken open a violent battle ensued between the termites and the ants (Ps. satanica). (43) Eutermes sp. Abandoned tunnels of another termite were found on the trunk and branches of an A. costaricensis bush inhabited by Ps. gracilis. Heteroptera (44) The only member of this order taken was a large Pentatomid, which was crawling on the foliage of A. costaricensis at Las Sabanas, Panama. Homoptera. Coccidse. Of this family I have found only three species associated with Acacias: (45) Coccus elongatus (Sign) (H. Morrison det.). A few specimens taken in spines of A. costaricensis inhabited by Ps. gracilis at Pueblo Nuevo, Panama. (46) Pseudococcus tcxensis Tinsley (H. Morrison det.). Numerous specimens taken in spines of A. veracruzensis, collected by Dr. A. Dampf at Vera Cruz, and inhabited by Crematogaster atra and corvina. (47) Pseudococcus sp. Inhabiting the cavities of flower-peduncles of A. Ilindsii which contained colonies of Solenopsis sp. Guatemala (Wheeler). Myriopoda. Two species of this class were found inhabiting old abandoned spines of A. costaricensis near Panama City, namely: (48) Polyxenus sp. Forming small colonies. (49) A Geophilus-like form, living singly. Araneina. At least four species of spiders were found inhabiting webs and concealing their egg-cocoons among the leaves and branches of A. costaricensis, and at least six in similar situations on A. melan- oceras. The following four have been identified by Mr. N. Banks. (50) Eustala fuscovittata Keys. On foliage of A. costaricensis at Punto Paitea, Panama. (51) Phyalc sp. On the same species of Acacia in the same locality. (52) Acrosoma obtusispina Keys. A large species inhabiting orb- webs among the branches of A. melanoceras at Marajal. (53) Nephila clavipes L. Another large spider inhabiting similar webs on the same species of Acacia. Acarina (54) Numerous mites found attached to the workers of wheeler: neotropical ant-plants and their ants 113 Camponotus brevis Forel inhabiting spines of A. costaricensis at Corazel, C. Z. Panama. Although the 54 different organisms, other than ants, above listed as associated with the bullhorn Acacias have been less satisfactorily studied and identified than those recorded for Cordia alliodora and Triplaris, and undoubtedly represent only a small fragment of the actual Acacia biocoenoses, they are sufficient, nevertheless, to show, first, that these plants have plenty of natural enemies and are in this respect like other nonmyrmecophytic trees and shrubs in the tropics, and second, that the obligate ant-tenants, though more virulent than those of Cordia alliodora and the Cecropias, are nearly or quite as tolerant of alien ants and other insects on the same plants. I therefore reiterate my statement of 1913 that the relations existing between the Acacias and the obligate Pseudomyrmas are not properly those of symbiosis, in which the plants have adapted themselves to the ants, but those of host and parasite, in which the adaptations are solely on the part of the ants. This contention, in its essential features, was rejected by Wasmann in his paper of 1915. Like other authors he has been greatly impressed by the coexistence of the capacious spines, abundant foliar nectaries and Beltian bodies in these Acacias, and though he is quite unable to account for these various structures, nevertheless regards the plants as having perfected them for the purpose of securing the protection of the ants. This is clear from the following quotation (p. 130): "If, therefore, we weigh the "pros and cons" of the so-called myrmecophily of the ant-acacias, I believe that we arrive at the same conclusion, which I had already reached in my previous paper (1915, p. 303, 315, 321), namely a position midway between the two extremes of an over- estimation and an underestimation of the myrmecophilous adaptations. The initiative that resulted in the occupation of the acacias by certain acacia ants of the genus Pseudomyrma, had its source in the latter. They selected these trees gradually with ever increasing regularity for purposes of establishing their colonies on account of the advantages accruing to their species. This specialization of the nesting instinct is, of course, to be conceived without any such anthropomorphism as that implied in supposing the ants to be aware of these advantages through intelligent reflection. Both the favorable domiciliary con- ditions, which the spines, of these trees afford the ants, and the favor- able nutritive conditions provided by the extrafloral nectaries, are therefore not a product of "natural selection" due to "adaptation" to the ants under consideration. The prerequisite physiological condi- 114 bulletin: museum of comparative zoology tions for these actual adaptations must have been developed before- hand by the laws of growth of the host-plants. But after certain species of Pseudomyrma had adapted themselves to these preconditions and had taken up their regular abode on the respective Acacias, it was possible, through the protection thus incidentally acquired by the host plant — even supposing this protection to be by no means considerable — that the further development of the extrafloral nectaries and especi- ally of the Beltian corpuscles was favored to a degree which the same peculiarities would not have attained without such rriyrmecophily. In this sense we may still speak of a true "symbiosis" between the ant- acacias and the acacia-ants, which is now more than a mere parasitism, though it arose origin ally from a unilateral parasitism. Somewhat similar conditions are found in the symphily of many myrmecophilous and termitophilous Coleoptera, which is also more than mere parasi- tism, though it had its beginning in unilateral parasitism." Of course, there is no way of either confirming or refuting this piece of pure phylogenetic speculation, which is so much like others in which Wasmann has indulged from time to time in regard to tropical organisms that he has never observed in a living condition. Obviously the ants could not have settled in the Acacias till their spines had developed to their present dimensions, and it was these organs, so easily convertible into domatia, that induced the ants to take up their abode on the plants. This is clearly indicated by two species of Acacia, among the many very diverse nonmyrmecophytic forms that grow in the same general geographical region, namely the swordthorns, A. macracantha Humb. and Bonpl. of Mexico, hirtipes Safford of Guate- mala, Standleyi Safford and gladiata Safford of Mexico and the spoon- thorns, cochliacantha Humb. and Bonpl. of Ecuador and cymbispina Sprague and Riley of Mexico and Central America. All these plants have large spines which are too much flattened to be used as domatia by the ants. I have not seen specimens of the various species but the following data collated from the literature indicate that food-bodies and nectaries like those of the bullhorn Acacias are present in at least some of them: A. macracantha, according to Standley (1922) has compressed spines 2.5 to 5 mm. long, but he makes no mention of food-bodies or nectaries. In A. Standleyi (Plate 44), according to Safford (1914), the young leaflets are tipped with food-bodies and the main leaf-rhachis bears "a conspicuous annular nectar-gland at the base of each pair of pinnae and usually one on the petiole, just below the lowest of these". The spines are "3-3.5 cm. long, 6-8 mm. broad at the base, very widely wheeler: neotropical ant-plants and their ants 115 divergent, the pair separated by a thickened ridge (the persistent base of the petiole) adnate to the branch." A. hirtipes. Nothing is said in Safford's description (1914) about food-bodies but the foliar nectaries are "dark purplish, circular, bowl- shaped, with a thick annular margin, one in the smaller leaves of the short branchlets, one borne at the base of each pair of pinna? and an additional one on the petiole ; on the larger leaves of the longer branches similar glands borne at the base of each pair of pinna? of the upper half of the leaf, but none in the lower half except a solitary gland on the petiole." The large stipular spines are "broadly v-shaped, cinereous, puberulent, except at the points, 3-4.2 cm. long, 10 mm. broad at the cuneate base, the latter flattened but not adnate to the branch as in A. Standlcyi." A. gladiata is considered by Standley as possibly merely a form of Standlcyi. The leaf-rhachis usually bears a nectary at its base and often one just below each pair of pinna?. The leaflets are "often muc- ronate or tipped with a waxy apical body, as in the true myrmecophil- ous acacias." "Large spines very long and divergent, usually flattened and sword-like, linear-lanceolate in outline, somewhat constricted at the base, resembling certain forms of the spines of Acacia cochliacan- tha H. & B. but connate instead of separate at the base and never split or inflated, gradually narrowed toward the apex to an acute point, 35 to 52 mm. long, 5 to 8 mm. broad, glabrous, reddish or wine-colored when young, at length brown or tan-colored." A. cymbispina. This form is usually identified as .4. cochliacantha, originally described from Ecuador, but is specifically distinct, accord- ing to Sprague and Riley. The spines are widely divergent and com- pressed, greatly enlarged and spoon-shaped, that is strongly convex on one side and concave on the other. This Acacia was observed by the Calverts (1917), who found it growing along the Bananita River, in Costa Rica. According to their account it resembled the bull's horn Acacia, "but had a less woody stem or trunk and paired thorns not curved nor inclined toward each other but merely at right angles to the stem bearing them. There were no little fruit-like bodies at the tips of the young leaflets, but along the midrib of each leaf was a row of urn-shaped glands, one at the base of the twenty-seven pairs of pinnae." There were no ants on this Acacia, "but it looked so much like bull's horn thorn as to suggest that it might be the starting point for the development of the latter." These cases show that the mere presence of well-developed foliar nectaries, or of nectaries and food-bodies, does not suffice to induce the 116 bulletin: museum of comparative zoology ants to make their abode in the Acacias. The same conclusion is also reached from observation of many other plants, such as the species of Cassia, Stillingia, Populus, etc. which may attract ants or other insects to their nectaries, but cannot retain them as permanent occupants, be- cause they possess no structures that can be converted into suitable domatia. It would be hazardous to maintain that A. cochleacantha and gladiata are either persisting, older, phylogenetic stages in the evolu- tion of the bull-horn Acacias or more recent, involutionary deriva- tives of the same. More probably the two species and their allies repre- sent independent developments from some stock common to that of the bull-horns ; and their survival as well as that of many more delicate species of Acacia in Mexico and Central America without ant-protec- tion, is not calculated to strengthen the contention of Wasmann and other believers in an adaptive myrmecophily on the part of the plants. Additional evidence of the absence of such adaptation is also available from the study of some of the African Acacias and of one South Ameri- can species, A. cavenia, to which we may now turn. (B) Acacia cavenia Hooker and Arnott We possess "three accounts of this Paraguayan Acacia, which really bears only a certain superficial resemblance to the bull-horns in the great enlargement of its spines and their occupation by ants. Fiebrig (1909) describes the plant as a shrub covering considerable areas in the Chaco of Paraguay, near the Bolivian boundary, and re- stricted to loess-like alluvial soil which is occasionally inundated and is not inhabited by Attine ants. Though the stems are so slender as rarely to exceed a centimeter in diameter, some of their stipular spines may become very large (90 mm. long and 8 mm. broad at the base), "but only at certain seasons, apparently as a result of abundant atmos- pheric humidity." Fiebrig found that their pith is devoured by a Tineid caterpillar, which before pupation gnaws an exit-hole near the tip of one of the spines of a pair. This caterpillar may hollow out not only a single spine but also its fellow and a portion of the adjacent stem. At the time of the moth's emergence the head of the pupa is pushed out of the opening. Later the spines are invaded by ants (Pseudomyrma fiebrigi Forel), which utilize the moth's exit-hole as an entrance. The young leaves of the Acacia bear no Beltian bodies. No mention is made of the presence of extra-floral nectaries. Previously, in 1896, Emery had described a number of ants taken by Dr. J. Bohls from the large spines of a Paraguayan Acacia, which wheeler: neotropical ant-plants and their ants 117 is almost certainly A. cavenia, since the specimens were collected in a locality, San Salvador, very near the Chaco in which Fiebrig made his observations. According to Emery, the species of Pseudomyrma made delicate galleries in the woody substance of the spines, whereas the species of Cryptocerus hollowed them out completely. "The opening of the Pseudomyrma nests was made near the tip of the spine, the openings of the other species were at a variable distance from the base and sometimes there were several." More recently A. cavenia has been studied again by Chodat and Vischer (1920) at Trinidad, Conception, etc. in the periodically inun- dated country along the Rio Paraguay. Their interpretation of the enlargement of the spines differs from that of Fiebrig, as will be seen from the following quotation and an examination of their figures 324 and 325 : "We have also found spines of considerable dimensions with- out any insect in them. One might ask, therefore, whether Fiebrig's theory is really sufficient to account for the production, or origin of these hypertrophied stipules. We suspected the existence of a morpho- genic stimulus produced by the sting of an insect in some other part of the stem, and we therefore sought for such organisms in the pith of the branches. Examination confirmed our suspicions. Below the insertion of the spines (stipules) we found the larva or pupa of a Chalcidid quite analagous to the one that produces the myrmecodomatia, or galls de- scribed for the Cordias. How does the infection occur. How does the female oviposit? The fissures indicate that the animal may penetrate the tissues either in the region of one of the buds or of its fellow of the opposite side. But this point should be observed at the time and place of its occurrence. The infection may be deep in the pith or more superficial (see Fig. 324). It will be noticed in Fig. 324 that the larva, after devouring a portion of the pith of the stem, moves towards the base of the spine, which becomes hypertrophied. Sometimes, as in the Cordias, two or several (?) larvse may be found. Moreover, the canal be means of which the larva penetrates the thorn, may be transverse and bring about a communication between the two stipules (see Fig. 325). Fiebrig had previously indicated the presence of these con- tinuous chambers or galleries but he assigned them an inverse origin. We are confirmed in our theory by the fact that Fiebrig himself noticed that the stipules may become hypertrophied without exhibiting any localized attack in their pith or base, that is, without any internal or external indications. For us, and we have made many concordant and no discordant observations, there is always an infection of the stem before the stipules are hollowed out. We must suppose, therefore, that 118 bulletin: museum of comparative zoology the excitation starts from the stem and is transmitted either by the plant tissue or by substances secreted by the animal, or, what is even more probable and agrees with most of our observations, by the direct action of the progressing larva. It may happen also, no doubt, that the infection is caused directly at the base of the leaf, since on one occasion we found a stipular spine that contained a pupa and a kind of cocoon, without any communication existing between the spine and the gallery in the stem." It would seem therefore, if this account be correct, that the en- larged spines of A. cavenia are really Hymenopterous galls and that the Tineid larva observed by Fiebrig is a secondary, or inquiline which feeds on their medullary tissue. The authors say nothing about the Tineids nor the ants which later inhabit the spines. The following are the ants that have been collected in these organs of A. cavenia: (1) Pseudomyrma acanthobia Emery (J. Bohls). (2) Pseudomyrma acanthobia var. fuscata Emery (J. Bohls). (3) Pseudomyrma ficbrigi : Forel (K. Fiebrig). (4) Crematogaster (Orthocrema) brevispinosa Mayr. (J. Bohls). (5) Leptothorax {Goniothorax) echinatinodis Forel subsp. spininodis Mayr. (J. Bohls). (6) Cryptocerus bohlsi Emery (J. Bohls). (7) Cryptocerus grandinosus F. Smith (J. Bohls). (8) Cryptocerus pcltat us Emery (J. Bohls). (9) Cryptocerus jnlosus Emery (J. Bohls). (10) Cryptocerus quadratus Mayr (J. Bohls). (11) Cryptocerus (Paracryptocerus) pusillus Klug (J. Bohls). (12) Cryptocerus (Cyathocephalus) pall ens Klug (J. Bohls). (13) Myrmelachista (Decamera) nodigera Mayr var. flavicornis Emery (J. Bohls). There is no evidence that any one of these species is an obligate tenant of A. cavenia. Many and probably all of them are generally found nesting in dead twigs or branches of other trees or shrubs. Even apart from this fact, there is nothing to indicate any "myrmecoph- ilous" peculiarities in the plant. (C) The African Acacias Some six different species of African Acacias {A. scyal Delile, dre- panolobium Harms, formicarum Harms, pscudofistula Harms, mala- cocephala Harms, and Bussci Harms) have been found to possess wheeler: neotropical ant-plants and their ants 119 greatly swollen spines inhabited by ants. Their consideration in this place may be greatly abbreviated both because I am dealing only with the Neotropical ant plants and because Bequaert (1921-22) has so recently and so adequately reviewed what is known in regard to the African Acacias. Most observers (Schweinfurth, Ascherson, Keller, Sjostedt, Glover Allen, Winkler, Schenck, H. Lang) of these plants in the field admit that the hypertrophy of their spines is really a gall- formation produced by Dipterous or Hymenopterous larvae. Bequaert gives the following reasons for adopting this interpretation: "They are not found on all specimens of the same species of Acacia, even in one locality; while on some plants practically all the thorns are swollen, others nearby bear hardly any galls; furthermore, their size is quite variable and their shape rather irregular. Mention may still be made of the fact that, while the species of Acacia enumerated above have a rather wide distribution in eastern Central Africa, swollen thorns have been noted in only a few localities within this range." The list of ants inhabiting the spines, as compiled by Bequaert, comprises 16 species (13 species of Crematogaster, one of Cataulacus and two of Tetraponera), and he adds: "As would be expected from the fortuitous production of galls on plants, none of the ants mentioned in the preceding pages seems to restrict the location of its nest to galls. They are evidently all arboreal species which are in the habit of shel- tering their brood in hollow branches or cavities of trees." l Chapter 7 VARIOUS NON-MYRMECOPHYTIC PLANTS WITH ANT-INHABITED STEMS, ETC. Among the vast number of Neotropical plants there are many that cannot be regarded as myrmecophytes though they furnish ants with sufficiently commodious living quarters (pseudodomatia) in their in- ternodes or other cauline structures. Several of these plants are so frequently or regularly inhabited as to be of special interest, at least to 1 Recent researches, which could not be considered by Professor Wheeler, throw a new light on the problem of the African ant Acacias. Paoli (1929 and 1930) studied two of the species, Acacia fistula Schweinfurth and A. Bussei Harms, in Somaliland. He found that these plants produce regularly two types of thorns. Some remain slender, while others slowly swell up at the base or over most of their length. The swelling is due to normal growth and is not induced by an insect. Eventually the pith of the swollen thorn dries up and the cavity thus produced may or may not be settled by ants. The swollen thorns are not insect galls but normal productions of the plant. The African ant Acacias are true myrmecophytes, but they lack the Beltian food-bodies of the American species. Both A. fistula and .4. Bussei bear small nectaries on the petioles, but these are also found on non-myrmecophilous Acacias. Paoli and Menozzi (1930) list many ants found in the thorns of the African ant Acacias. [J. Bequaert 120 bulletin: museum of comparative zoology the collector. The simplest cases are those in which the internodes be- come hollow by disappearance of their pith before they are occupied. In others the ants clean out the pith and in still others they occupy burrows that have been more or less extensively excavated by wood- boring beetle larva?, caterpillars, etc. The data cited in the literature often leave doubt as to which of these conditions obtains in a particular instance. The predilection of the ants for certain species of plants with inhabitable stems is probably enhanced by the regular development of extrafloral nectaries or the frequent occurrence of particular Coccids on their shoots or foliage. In the following paragraphs I have brought together a number of records on Neotropical plants that frequently have ant-inhabited stems, etc. There are, of course, several woody plants in temperate regions, like the common elder of our Northern and the white ash of our Southern states, the English walnut and blackberry in Switzerland, etc. which are similarly tenanted by a num- ber of Formicida?, but these plants I have not included. 1 I have also omitted the galls of oaks and other plants, which after serving for the development of their makers, often furnish convenient habitations for small colonies of ants, especially of the genera Leptothorax, Cremato- gaster and Camponotus (subgenera Myrmentoma and Colobopsis), etc. both in Europe and North America. Graminese and Cyperacese Bamboos. The hollow internodes of various bamboos are sometimes inhabited by ants, but this occurrence seems to be rather local. In the large Javanese bamboos surrounding the tropical laboratory at Kar- tabo, B. G. I failed to find any ants, and examinations of the smaller species in that region were equally negative. Lutz, Forel, Luederwaldt (1926) and other collectors in Brazil and H. Schmitt in Costa Rica, however, have found quite a series of bamboo-inhabiting forms. The following is a list of the recorded species: (1) Eclton (Acamatus) legionis F. Smith. Abundant in bamboos (in temporary nests?). Brazil (Garbe). ( 2) Acanthoponera dolo Roger. Brazil (Luederwaldt). ( 3) Neoponera crenata Roger. Brazil (Luederwaldt). Occupying nests made by Camponotus albo-anmdatus. 'See Stager's interesting paper (1917) on the stem inhabiting ants of Switzerland. He records seven different forms, belonging to the genera Leptothorax, Crematogaster, Dolichoderus (Hypoclinea) and Camponotus (Colobopsis), as living in the stems of Rubus ulmifolius. Three of these forms occur also in walnut twigs. In all cases the ants invade cavities previously excavated by solitary wasps (mainly Crabronids), solitary bees (Ceratina) and beetles. wheeler: neotropical ant-plants and their ants 121 ( 4) Neoponera crenata var. moesta Mayr. Brazil (H. Luederwaldt). ( 5) Pseudomyrma gracilis Fabr. subsp. mexicana Roger. In Bam- busa. Costa Rica (H. Schmitt, cited by Menozzi, 1927). ( 6) Pheidole bambusarum Forel. Brazil (A. Lutz; Luederwaldt). ( 7) Pheidole guilelmi-muelleri Mayr subsp. avia Forel. ( 8) Pheidole lutzi Forel. Brazil (A. Lutz; Luederwaldt). ( 9) Solenopsis saevissimaF. Smith. Brazil (H. Luederwaldt). (10) Solenopsis franki Forel subsp. idee Forel. Brazil (H. Lueder- waldt). (11) Crematogaster (Orthocrema) brevispinosa Mayr. Costa Rica (H. Schmitt). (12) Crematogaster (Orthocrema) curvispinosa Mayr. Costa Rica (H. Schmitt). (13) Crematogaster (Orthocrema) distans Mayr. subsp. parviceps Forel. Brazil (Luederwaldt). (14) Crematogaster (Orthocrema) lutzi Forel. Brazil (A. Lutz). (15) Crematogaster (Orthocrema) quadriformis Mayr. In Guadua distorta. Brazil (Luederwaldt). (16) Cryptocerus maculatus F. Smith. In Bambusa. Costa Rica (H. Schmitt). (17) Cryptocerus (Paracryptoccrus) minutus Fabr. In Bambusa. Costa Rica (H. Schmitt). (18) Cryptocerus (Cyathocephalus) segidifer Emery. In Bambusa. Costa Rica (H. Schmitt). (19) Cryptocerus (Cyathocephalus) varians F. Smith subsp. margina- tus Wheeler and Mann. Haiti (W. M. Mann). (20) Iridomyrmex iniquus Mayr. In bamboo: Brazil (H. Lueder- waldt). (21) Iridomyrmex iniquus var. succinea Forel. Brazil (Luederwaldt). (22) Iridomyrmex leucomelas Forel. Brazil (Luederwaldt). (23) Tapinoma atriceps Emery. Brazil (A Lutz; Luederwaldt). (24) Tapinoma atriceps var. breviscapa Forel. Brazil (A. Lutz; Luederwaldt) . (25) Myrmelachista (Decamera) bambusarum Forel. Brazil (Goeldi). (26) Myrmelachista (Decamera) paderewshii Forel. Brazil (A. Lutz). (27) Camponotus (Tanosmyrmex) lutzi Forel. Brazil (A. Lutz). (28) Camponotus (Myrmothrix) cingulatus Mayr var. bambusarum Forel. Brazil (Goeldi; Luederwaldt). (29) Camponotus (Myrmomalis) emeryodicatus Forel. Brazil. Lueder- waldt). 122 bulletin: museum of comparative zoology (30) Camponotus (Myrmobrachys) planatus Roger var. acacia? Emery. In Barabusa. Costa Rica (H. Schmitt). (31) Camponotus (Pseudocolobopsis) alboannulatus Mayr. In Bam- busa taquara Nees. Brazil (Luederwaldt). (32) Camponotus (Hypercolobopsis) paradoxus Mayr subsp. janitor Forel. Brazil (A. Lutz); in Bambusa taquara Nees and allied species (Luederwaldt). Luederwaldt also records two Coccids, Lachnodiella taquara' Hemp, and Orthezia grandis Hemp., living with Pheidole lutzi in the bamboo internodes. Uniola and Cladium. In the Bahamas I frequently took colonies of the following ants in the culms of a large grass, Uniola paniculata L., and a sedge, Cladium jamaiecnse Crantz : (1) Pseudomyrma elongata Mayr. (2) Pseudomyrma flavidulaY. Smith (3) Macromischa splendens Wheeler (4) Crematogaster (Acrocatlia) lucayana Wheeler (5) Cryptocerus (Cyathocephalus) varians F. Smith (6) Tapinoma littorale Wheeler (7) Camponotus (Colobopsis) culmicola Wheeler According to Stager (1917), the regular occurrence of ants in the culms of grasses in the savannahs of Colombia was noticed by E. A. Goeldi as early as 1896. I have found various species of Pseudomyrma, especially Ps. flavidula, in the same situations in Panama and British Guiana. Scitaminese Crematogaster (Orthocrema) limata F. Sm. subsp. parabiotica Forel, which is associated with so many different plants, is also recorded as living in the inflorescences of a species of Costus in Amazonas (E. Ule). Orchidacese Many of the epithytic species of this huge family undoubtedly harbor ants either about their roots, between the plants and their sup- port, or in the pseudobulbs, but unfortunately many of the observa- tions lack precision and the ants have rarely been identified. Bequaert (1921-22) includes only two Neotropical genera, Diacrium and Schom- burgkia, among the myrmecophytes. He remarks that "D. bicornutum (Hooker), of Trinidad and Guiana, has a swollen spindle-shaped stem which is normally hollow and perhaps regularly inhabited by ants wheeler: neotropical ant-plants and their ants 123 (Rodway, 1911, p. 111). Schlechter claims that even under cultivation the pseudobulbs form at their base a slit through which the ants gain access into the cavity." The pseudobulbs of several species of Schom- burgkia are also described as hollow and ant-inhabited. I find that only the following ants have been identified as orchid tenants: (1) Neoponera villosa F. Smith. In pseudobulbs of Schomburgkia tibicinis Bateman. Mexico (G. Mayr). (2) Monomorium floricola Jerdon. In pseudobulbs of Epidendrum imatophyllum Lindl. Honduras (O. Ames). (3) Crematogaster (Orthocrema) armandi Forel. In pseudobulbs of an orchid. Brazil (S. Moore). (4) Crematogaster (Orthocrema) limata F. Sm. subsp. parabiotica Forel. In pseudobulbs of Diacrium bilamellatum Hemsl. Panama (Wheeler). (5) Azteca tonduzi Forel. In pseudobulbs of an orchid. Costa Rica (Tonduz). (6) Azteca velox Forel subsp. nigriventris Forel. In pseudobulbs of Diacrium bicornutum, "in constant symbiosis". Costa Rica (P. Biolley). (7) Dolichoderus (Monads) bispinosus Olivier. Nesting in a tuft of orchids. Costa Rica (P. Biolley). Polygonacese Coccoloba uvifera (L.) Jacq. — This peculiar tree, the "seagrape", is very common along the beaches of tropical Florida and the West Indian islands. As a rule it is less than 15 ft. high, but in exceptional cases may attain a height of nearly 50 ft. with a trunk more than a yard in diameter. The peculiar, leathery, shining, orbicular or even trans- versely elliptical leaves make it a quaint and conspicuous object among the littoral vegetation. The foliage is a source of food for a number of miscellaneous insects and the following ants not infrequently inhabit its short, hollow internodes: (1) Pseudomyrma elongata Mayr. Bahamas (Wheeler). (2) Pseudomyrma elongata var. cubaensis Forel. Cuba (Wheeler). (3) Cryptocerus (Cyathocephalus) varians F. Smith. Florida (Miss Nancy B. Fairchild). (4) Tapinoma melanocephalum Fabr. Cuba (Wheeler). (5) Myrmelachista ambigua Forel subsp. ramulorum Wheeler. Porto Rico (Wolcott). The "hormiguilla", a pest of the coffee plantations. 124 bulletin: museum of comparative zoology (6) Camponotus (Tancemyrmex) ramulorum Wheeler. Bahamas and Cuba (Wheeler). (7) Camponotus (Tanamyrmex) ramulorum var. marcidus Wheeler. Bahamas (Wheeler). (8) Camponotus (Tancemyrmex) ustus Forel. Porto Rico (W 7 heeler). (9) Camponotus (Myrmobrachys) planatus Roger. Cuba (Wheeler). (10) Camponotus (Myrmosphincta) sexguttatus Fabr. Porto Rico (Wheeler). The following insects have been recorded by Wolcott (1923) as in- festing C. uvifera in Porto Rico: (1) Dichomeris zingarella Walsh. Gelechiid moth reared by Busck. (2) Ctenodactylomyia watsoni Felt. Cecidomyid fly reared from galls by R. H. van Zwaluwenburg. (3) Cryptoccphalus perspicax Weise. Chrysomelid beetle feeding on foliage. (4) Attelabus coccolobce Wolcott. Curculionid beetle feeding on foliage. (5) Exophthalmodes roseipes Chevr. Curculionid beetle feeding on young foliage. (6) Lachnopus curvipes Fabr. Curculionid beetle on foliage. (7) Tangia sp. Fulgorid. (8) Ormenis marginata Brunnich. Fulgorid. (9) Ormenis pygmcea Fabr. Fulgorid. (10) Cyarda sp. Fulgorid. (11) Pseudococcus nipa Maskell. Coccid. Coccoloba rugosa Desf . The few specimens of this plant which I saw in Porto Rico, were small trees with very slender trunk and few branches and enormous, coarse, cordate clasping leaves, (30-60 cm. broad!) among the large veins of which, on the lower side and at the base, a small yellow ant, Iridomyrmex melleus Wheeler builds fragile carton nests. More frequently, however, this insect inhabits the hollow twigs of a variety of plants. In South America Spruce (1869, in 1908) observed a number of ant- inhabited Coccoloba species as well as several other Polygonaceous genera (Campderia, now included in Coccoloba, Lymmeria, Rup- prechtia and Triplaris, which has been considered at length (p. 41 et. seq.) All these, he says, "grow in moist situations, and most of them on lands subject to inundations. Not only is every lignescent Poly- gonea a habitation for ants, but the whole of the medulla of every plant, from the root nearly to the growing apex of the ramuli, is scooped out by these insects." These are species of Pseudomyrma, which are wheeler: neotropical ant-plants and their ants 125 known in Brazil by the name of "Tachi" of "Tacyba" and in Peru by that of "Tangarana"; and in both countries the same name is com- monly applied to any tree they infest as to the ants themselves." One of the species of Coccoloba he mentions in particular: "Some Tachi trees seem as if they were actually trying to run away from the ever encroaching ants. Coccoloba parimensis Benth., found by Schomburgk in British Guiana and by myself on the Rio Uaupes, is an arbuscle with a stem 15 feet long, that tapers upwards and arches over so as finally to touch the ground, the ants all the while hollowing it out, as it stretches away apparently in the hopeless attempt to escape their invasion. Some slender Coccolobas climb high into the adjacent trees, not by twining but by crooking their branches and thereby hoisting them- selves up ; others are self-standing bushy trees, but still have the same slender geniculate branches." Bixacese Bixa orellana L. This bush or small tree, the "achiote anatto" or "anotto", reaches a height of 30 feet and is common throughout the West Indies and Central America. It is also cultivated both in these regions and in the East Indies, because the testa of its seeds yields a beautiful orange-red pigment, the famous "anatoo" dye. Pittier (1908) gives a good account of the plant. "Bixa orellana, a tree of even elegant aspect, with rose-colored, rather conspicuous flowers and capsular fruit covered with soft spines and containing numerous seeds. The outer integument, or tests of these seeds contains a yellowish red coloring matter, which is extracted with hot water and may be decom- posed, according to Chevreul, into two pigments, buxine, which is yellow, and orelline, which is red. "Bixa orellana seems to be indigenous through tropical America and has been cultivated like the cacao plant from the most remote times. It easily matures its fruits up to an altitude of 1200 m. The wild form, or Achiote simarron, with smaller leaves and less developed floral organs, is found in Costa Rica in the woods of the Pacific slope up to an altitude of about 800 m. The dye which is fast and brilliant, was used by the natives to stain their bodies and also to tint their clothes and various other objects. At the present time it is employed in coloring butter, certain kinds of cheese, sarozas and other fabrics. In the Creole Kitchen it is used to color rice. "The word achiote, which designates both the tree and the red, resinous paste extracted from the outer integument of the seeds, is a 126 bulletin: museum of comparative zoology corruption of the Nahoutl achiotl. In the Guyanas, the Indians call the tree and its product uruau, whence the French rocou is derived. Anatto and bija are other names applied to the coloring matter." I found this plant rather common in Panama, both in the gardens at Ancon and Balboa, and wild, especially on the Atlantic side of the Isthmus near Colon, Marajal and on Barro Colorado Island. The leaves are broad and subcordate and covered with microscopic glands beneath, while the petiole bears at its junction with the blade a distinct thickening with a pair of large nectaries, which are visited by the ants. It is not surprising to find, therefore, that the short internodes are frequently inhabited by these insects. These internodes have to be hollowed out by the ants, since they contain a persistent pith. A careful study of the plant in different localities will probably yield quite a number of different ants. The following list includes those collected in Panama and two forms recorded by Forel (1906) as taken in Costa Rica: (1) Pseiidomyrma flavidula F. Smith var. capperi Forel. In twigs, Ancon, C. Z. (Wheeler). (2) Pseiidomyrma gracilis Fabr. In twigs. Marajal, C. Z. (Wheeler). (3) Pseiidomyrma ehngata Mayr. var. tandem Forel. In the trunk and fruits. Costa Rica (P. Biolley). (4) Pseiidomyrma serieea Mayr var. ita Forel. In trunk and leaves. Costa Rica (P. Biolley). In twigs. Barro Colorado Isl. (Wheeler). (5) Crematogaster (Orthocrema) brevispinosa Mayr. Feeding at foliar nectaries. Ancon, C. Z. (Wheeler). (6) Crematogaster (Orthocrema) brevispinosa var. ampla Forel. In twigs. Barro Colorado Isl. (Wheeler). (7) Leptothorax (Goniothorax) cchinatinodis Forel var. cordincola Wheeler. In twigs. Barro Colorado Isl. (Wheeler). (8) Cryptocerus (Par aery ptocerns) miniitus Fabr. In twigs. Barro Colorado Isl. (Wheeler). (9) Dolichoderus (Hypoclinea) ehampioni Forel subsp. trinidadensis Forel var. tceniatus Forel. In twigs. Marajal C. Z. (Wheeler). (10) Tapinoma mclanocephalum Fabr. In twigs. Ancon, C. Z. (Wheeler). (11) Paratrechina longicornis Latr. Feeding at nectaries. Ancon, C. Z. (Wheeler). (12) Camponotus (Myrmobrachys) zoc Forel. In twigs. Barro Colorado Isl. (Wheeler). (13) Camponotus (Pseudocolobopsis) claviscapus Forel. In twigs. Marajal, C. Z. (Wheeler). wheeler: neotropical ant-plants and their ants 127 The general insect fauna of B. orellana has not been studied, but is probably quite as abundant as that of many other tropical trees. Two species of Coccids, Howardia biclavis Comst. and Inglisia vitras Cockerell, are cited by Wolcott (1923) as infesting the plant in Porto Rico. Marcgraviacese The types of Azteca longiceps Emery subsp. juruensis were taken by E. Ule in the twigs and branches of a species of Schwartzia (Norantea) in Amazonas. The juvenile stages of the species of Marcgravia have the form of peculiar creepers which adhere to the trunks of trees or the surfaces of rocks. On each side of the reptant stem is a regular series of round- elliptical leaves which are also rooted to their support and leave very narrow spaces between the latter and their lower surfaces. In a plant running over rocks in the island of Dominica, W. I., I found numerous colonies of Wasmannia auropunctata Roger utilizing these spaces for nesting purposes. I believe that Forel (1899-1900) must have taken the type specimens of his Azteca hypophylla in such quarters under the leaves of some species of Marcgravia in Colombia, since he de- scribes the insect as making "its nest under the round leaves of a plant which climbs on tree trunks like ivy. The ant glues the edges of each leaf to the bark of the tree with carton." Combretacese Terminalia catappa L. This fine tree, known as the Indian or Malabar almond and in tropical America, where it is often planted for shade, as the "almandra" is easily recognized by its peculiar shining, obovate leaves, about 15 to 20 cm. long, with narrow cordate base and short petiole, clustered at the ends of the branches. The small white flowers are in slender spikes and the drupe-like, edible fruit has the shape of an almond. The internodes of its terminal twigs are often hollowed out and inhabited by ants. I have collected the following species from the trees planted along the drives at Balboa and Fort Amador, C. Z. Panama: (1) Pseudomyrma zebelli Forel. (2) Solenopsis laeviceps Mayr var. antoniensis Forel. (3) Solenopsis zeteki Wheeler. (4) Crematogaster (Orthocrema) brevispinosa Mayr var. arnpla Forel. 128 bulletin: museum of comparative zoology (5) Cryptocerus (Paracryptocerus) minutus Fabr. (6) Dolichoderus (Hypoclinea) lutosus F. Smith. Although T. catappa is not a native of the American tropics it is nevertheless attacked by several insects, as shown by the following data collected by Wolcott (1923) in Porto Rico: (1) Mcgalopyge krugii Dewitz. Megalopygid moth, feeding on foliage. (2) Oeceticus kirbyi Guilding. Psychid moth cited by Gundlach as feeding on foliage. (3) Attelabus sexmaculatus Chevr. Curculionid beetle, feeding on foliage. (4) Aspidiotvs destructor Sign. Coccid. (5) Pseudococcus virgatus Ckll. Coccid. (6) Saissetia nigra Nietn. Coccid. (7) Saissetia oleoe Bernard. Coccid. (8) Chrysomphos aonidum L. Coccid. In the twigs of another Terminalia, T. (Bucida) buceras Wright, in Porto Rico, I have taken colonies of the "hormigilla", Myrmelachista ambigua subsp. ramulorum. Bombacaeeae Probably the twigs of several of the large arborescent species of this family, especially the various silk-cotton trees, are not infre- quently inhabited by ants, but I can cite only two records in support of this statement. J. Huber and A. Goeldi found twigs of Bombax mungaba on the Rio Purus, Amazonas, inhabited by Pseudomyrma sericea Mayr., and recently Prof. Jack, of the Arnold Arboretum, has brought me from Soledad, Cuba a number of twigs of the common Ceiba tree, Ceiba pentandra, containing colonies of Pseudomyrma elongata Mayr var. cubaensis ForeL Euphorbiaceae Mabea. About 30 species of this genus are known from Brazil and the Guianas. They are shrubs with flexuous hollow branches, and some of the species, especially M. fistulifera Mart, and angustifolia Benth., seem to be well-supplied with calyx-glands, or glands on the branches of the flower panicles (M. occidentalis Benth). The latex of M. piriri Aubl. of the Guianas yields rubber, and the stems of both it and M. fistulifera are made into tobacco-pipes, as described in the following quotation from Spruce: "The Mabeas are still more remark- wheeler: neotropical ant-plants and their ants 129 able than the Tachias, the long sarmentose branches stretching away to a great length among the adjacent vegetation, although never actually twining. All Mabeas of the section Taquari have this habit, and all are infested by Tachi ants. The slender but tough twigs, hollowed and polished internally by ants, are a favorite material for tobacco-pipes with the Indians of the Amazon, who strip off the bark and paint and varnish the surface of the wood. These "Taquaris", as they are called, are commonly sold in the shops of Para. A bundle of them which I purchased there is now in the Kew Museum. The arborescent Mabeas, however, with tall erect trunks and paniculate inflorescence, are apparently never touched by ants." Sapium. Also a fairly large genus, comprising 25 species, and occurring in both the Old and New World tropics. The petioles have a pair of nectaries at their junction with the leaf-blade. The latex of S. biglandulosum Aubl. is medicinal and is said to yield a kind of rubber, but that of some of the Panamanian species (probably S. aucup- arivm Jacq.) is, according to Standley (1928 p. 240), "chewed by boys, i who place it on twigs for the purpose of catching small birds." Azteca longiceps Emery subsp. sapii Forel was taken by Ducke in the hollow stems of S. glandulosum Morong at lea, Amazonas, and Pseudomyrma caroli Forel var. sapii Forel was taken by E. Ule in the hollow stems of an undetermined species of Sapium at Bom Fim, Jurua, Amazonas. Alchornea. This genus contains about 30 species of frutescent or arborescent plants which, like those of the preceding genus, occur in the tropics of both hemispheres. The leaves are described as bearing two to several nectaries at the base on the lower side. A. irucurana Casar of the subgenus Eualchornea is called "irucurana" or "arariba" by the Brazilians and yields a valuable wood. The following ants have been taken in its branches by K. Fiebrig in Paraguay : (1) Pseudomyrma sericea Mayr var. ita Forel. (2) Forelius maccooki Forel var. brasiliensis Forel. (3) Forelius maccooki subsp. fiebrigi Forel. (4) Azteca luederwaldti Forel. Leguminosae The genera of this huge family, besides Tachigalia, which have been cited as containing species tenanted by ants in the New World are Sclerolobium, Pterocarpus and Platymischium: Sclerolobium. According to Spruce, "the species of Sclerolobium are 130 bulletin: museum of comparative zoology not usually riparian but one species (S. odoratissimum sp. no v.) is eminently so, constituting a great ornament of the shores and islands of the Rio Negro towards the mouth of the Casiquiari, and perfuming the whole breadth of the river with the abundance of its pale yellow honey-scented flowers; and it is notable that this is the only species of the genus in which I have found sacciferous petioles. The sac is large, extending upwards from the knee of the petiole to the base of the second pair of leaflets, and it has a furrow along the upper surface. I presume the ants have been induced to take up their residence on these particular plants on account of the abundance and long per- sistence of their honied flowers." Bequaert believes that the petiolar sac described by Spruce "is merely an insect gall which, when empty, becomes settled by ants." In two other species, S. tinctorium Bentham and panieulatum Yog., Spruce observed no such domatia but merely the infestation of the flower-panicles "with little fire-ants, which, however, seemed to have their permanent habitation in the ground about or near the tree-roots, and never to perforate the leaf-stalks." Pterocarpus. A genus comprising some 20 species of tropical trees with hard wood of considerable economic value and yellow flowers. Spruce alludes to P. ancylocalyx Bentham as "a small tree on the banks of the Solimoes, or Upper Amazon, which has the rachis of the racemes thickened in the middle, the swelling being sometimes (but not ways) tenanted by ants." Forel (1904) cites Pseudomyrma sericea Mayr as having been taken by E. Ule in the swollen flower-axes and twigs of P. ulei Harms at Jurua Miry, Amazonas. Platymischium. A Neotropical genus comprising trees or shrubs with yellow flowers. In at least some of the 15 known species the stems are hollow or even dilated at the nodes and inhabited by ants. The following species have been recorded: (1) Pseudomyrma picta Stitz var. heterogyna Wheeler. In Platymis- chium sp. Bolivia (W. M. Mann). (2) Pseudomyrma sericea Mayr var. longior Forel. In P. stipulate Bentham. Amazonas (E. Ule). (3) Cryptocerus (Paracryptocerus) complanatus Guerin subsp. rami- philus Forel. In P. ulei Harms. Amazonas (E. Ule). (4) Azteca huberi Forel. In Platymischium sp. Brazil (J. Huber). Perhaps some of the species of the genus Cercidium may prove to harbor several species of ants in their twigs and branches. Cryptocerus rohweri Wheeler, at least, has been taken from the branches of C. torreyanum in Arizona. wheeler: neotropical ant-plants and their ants 131 Olacacese Agonandra. In Paraguay Chodat and Vischer (1920) found two species of ants, Crematogaster (Orthocrema) goeldii Forel var. chodati Forel and Cryptocerus eduarduli Forel, nesting in the trunks of A. brasiliensis Benth. and Hook., a dioecious tree with pendent twigs, thin, elliptical, pointed leaves and small, racemose flowers. These botanists promise a fuller account of the plant and the nesting habits of the ants and merely remark (p. 193): "The material which we brought back from Paraguay for the purpose of studying the myrme- cophily of the Agonandra, does not permit us to reach such precise (sic!) conclusions from this genus as those obtained from the Cordias and Acacia cavenia. In fact, in the trunks of this species, the existence of medullary galleries with rather large openings excavated perpendic- ularly to the wood can be observed only at certain points. It seemed to us that these galleries had been excavated by some phytophagous insect, possibly a Coleopteron." It is difficult to see how "myrme- cophily" can apply to this case any more than to the excavations made by Camponotus herculeanus L. and its various races in the wood of North American and European trees which have been previously attacked by various beetles. Loranthacese Phoradendron. In Arizona I found the stems of a mistletoe, Ph. flavescens Nutt. var. villosum Nutt., growing on live oaks (Qucrcus emoryi) to be regularly inhabited by colonies of Crematogaster (Ortho- crema) arizonensis Wheeler. According to Schwarz (1901) the cavities tenanted by the ants are made by a Curculionid beetle of the genus Otidocephalus. The plant, indeed, constitutes the center of an inter- esting biocoenose, comprising a Coccid, Pseudococcus phoradendri Cockerell, which lives in the cavities with the ants, another Coccid, Lecanium phoradendri which, according to Schwarz, lives on the outer surface of the plant, a Coccinellid beetle, Cephaloscymnus occidentalis florn, that feeds on this Coccid, a butterfly caterpillar, Thecla halesus, that consumes the leaves and two beetles, a Bostrychid (Amphicerus sp.) and a Scolytid (Stephanoderus sp.) that bore in the stems. Rutacese Xanthoxylon. Many years ago I found that the twigs of the common prickly ash of our Southern States, X. clavis-Herculis L., in the vicinity of Austin, Texas were frequently inhabited by colonies of three species 132 bulletin: museum of comparative zoology of Pseudomyrma (Ps. brunnea, flamdula and pallida), and more recently Mr. E. D. Christophersen has found two species of ants, Pheidole gauthieri Forel var. oxymora Forel and Camponotus (Hypcrcolobopsis) christophcrseni Forel, living in the large, corky spines which stud the trunk of X. panamense P. Wils. Although I have often examined the spines of this Central American tree and have found in many of them galleries that had been eaten out by insects, I failed to find any ant-colonies. The species taken by Christophersen may have been chance occupants of such burrows. Anacardiacese Schinus. Luederwaldt (1926) records the occurrence of Procrypto- cerus subpilosus F. Smith subsp. lepidus Forel in dry excrescences on Schinus terebinthifolius Raddi in Brazil. Rubiacese Borreria verticillata (L.) G. F. W. Mey. As previously stated (p. 92) the hollow, internodes of this low shrub are often inhabited by ants. I first observed it in a small clearing, covering less than an acre, behind the tropical laboratory at Kartabo, B. G., where it was very abundant. Its small, agglomerated flowers attracted many bees, especially Meli- poninse, and the dead stems seemed to be even more frequently occu- pied by ants than those of any other plants in the vicinity. According to Schumann (1897 p. 114), B. verticillata is common in the warmer parts of America from Florida and Mexico to Argentina, not rare in West Africa and on the Cape Verde Islands and has been recorded from Mozambique. The following is a list of the ants taken in its internodes at Kartabo : (1 (2 (3 (4 (5 (6 (7 (8 (9 (10 (11 (12 (13 (14 Pseudomyrma acanthobia Emery Pscudoviyrma Pseudomyrma Pseudomyrma Pseudomyrma gracilis Fabr. Monomorium Solenopsis corticalis Forel Crematogaster Lcptothorax (Goniothorax) aculeatinodis Emery Leptothorax (Goniothorax) spininodis Mayr Cryptocerus maculatus Fabr. Myrmelachista Brachymyrmex Campo?iotus wheeler: neotropical ant-plants and their ants 133 Gentianacese Tachia. The only Neotropical genus of this family said to be asso- ciated with ants is Aublet's Tachia (Myrmiecia Schreber). In the original description of the type species, T. guianensis, Aublet states that "the trunk and branches, which are hollow, serve as a retreat for ants; it is for this reason that this shrub is called by the Galibis 'Tachi', which according to their report, signifies in their language "ant-nest". According to Spruce, "the pretty Gentianaceous shrubs of the genus Tachia have long, slender, hollow branches, that either hang down or support themselves on the branches of adjoining shrubs and trees; yet although this character is (as I suppose) an undoubted inheritance of the effects of ant-agency, it is singular that Tachias are now-a-days often found entirely free from ants; while the name taken by Aublet from the Tupi language, distinctly implies that in his day they were notoriously ant-infested." These remarks seem to indicate that the Tachias are not myrmecophytes but shrubs sometimes or per- haps only locally inhabited by ants. I have seen no record of Formi- cidre from these plants. Composite The sole Neotropical representative of this huge family recorded as harboring ants is the Brazilian Erigeron maximus Link. H. von Ihering and Luederwaldt found its stalks inhabited by Azteca muelleri Emery var. wacketi Emery. Like the typical form of the species, this variety also makes carton nests in the trunks of Cecropia. Chapter 8 THE EPIPHYTIC BROMELIACE^E AND THEIR FAUNA Some years ago considerable attention was devoted to a study of the epiphytic Bromeliaeese of the Neotropical Region, but there are few references in the literature to their ant-inhabitants. Several botanists, notably Cedervall (1884), Schimper (1884, 1888, 1903), Ule (1900), Mez (1904), Werckle (1909) and Aso (1910), investigated the anatomy and ecology of these epiphytes, and quite a number of zoologists, including Fritz Miiller (1879, 1880), Ad. Lutz (1903), Calvert (1910a, 1910b, 1911a, 1911b, 1917) Scott (1912), Knab (1912, 1913a, 1913b) and Picado (1911, 1912a, 1912b, 1913) were keenly interested in the associated faunal components. 134 bulletin: museum of comparative zoology Most of the Bromeliacese are epiphytes on living trees or shrubs, but some of them occasionally grow on inanimate supports, such as rocks, fences, telegraph-wires, etc., and although the majority of the genera and species are confined to the rain-forests, certain species, especially of the genus Tillandsia, flourish in dry, open forests or coppices or along sea-beaches. The plants lack stems and their slender roots serve merely for holding fast to the substratum. Many species, however, if they happen to be detached from their support, readily take root in the soil and continue their growth under the new conditions. The leaves grow in the form of a close rosette and are widened at their bases, which are arranged in such a manner that each can receive and retain a certain amount of water, derived from the rain, dew or mist, and both inor- ganic and organic detritus (windblown leaves, soil, etc.). Some large Bromeliads may thus store as much as 20 litres of w T ater. On this account the epiphytic Bromeliacea? have been called "tank-epiphytes" (Schimper, 1903) and may be regarded as so many diminutive pools, which in the tropics replace the ponds of more temperate regions (Picado, 1913). The flowers, often showy though evanescent, are usually borne on a long leafy or scaly axis arising from the center of the leaf-rosette. The fruits are very diverse, being in some species berries, in others dehiscent pods. Peculiar appendages in the form of asymetrical wings or crests or pappus-like tufts of silky hairs are de- veloped from the walls of the capsule and serve to disseminate the seeds, which are usually numerous but differ considerably in shape in the various genera. Owing to the peculiar arrangement of the leaves and their method of retaining water and detritus, the plant, according to Picado, may be divided into an aquarium, or tank, and a terrarium; the former represented by all the water-holding leaf-bases, the latter by the dry detritus which is left over around the periphery after the older outer leaves of the rosette have decayed or broken off and therefore no longer hold water. Both the tank and the terrarium furnish habitations for a large number of organisms, the tank for many aquatic and amphibi- ous creatures (Infusoria, fly, beetle, and dragonfly larvae, Copepods, tree-frogs, etc.), the terrarium for many cryptobiotic forms (worms, Isopods, earwigs, Myriopods, Onychophora, etc.). Ad. Lutz believes that fully one fifth of the species of Brazilian mosquitoes, including some nosophoric (malarial) forms, regularly breed in the tanks of Bromeliacea? and Knab has bred a number of Culicidse from these plants in Mexico and Panama, including the large species of Megar- hinus, which are so cannibalistic as larvse that only one of them can wheeler: neotropical ant-plants and their ants 135 live in a single water-holding leaf-base. The foliage of the Bromeliads, of course, affords food for several caterpillars and leaf-eating beetles, bugs, etc., and opportunities for various spiders to construct their webs and prey on the small Diptera that oviposit in the tanks. Ad. Lutz discovered that the water in the reservoirs is unusually pure and that no putrefaction of its organic contents takes place as long as it remains in contact with the plants' leaves. It has long been known that the latter are covered with peculiar shield-shaped scales (modified trichomes), which are always most abundant at the leaf- bases and have been carefully studied by Cedervall, Schacht, Schim- per, Mez and Aso. Schimper showed that the water as well as its contained salts and organic substances are absorbed by the leaves through these scales and are essential to the growth of the plant. He states that "the spoon -shaped leaf-bases, which are closely applied to one another, nearly always contain even during the dry season con- siderable quantities of water, pieces of rotting leaves and twigs, dead animals and earthy materials of undeterminable origin. Experiments have shown that these substances arc not only utilized by the plant but are indispensable to its existence, since the roots, under the most favor- able circumstances, take up but little water to cover transpiration and besides under natural conditions usually remain quite dry on account of the umbrella-like form of the leaf-rosette." Most epiphytic Bromeliads are strongly negatively geotropic and therefore grow in such a position that their leaves are able to acquire and retain considerable quantities of meteoric water and both mineral and organic detritus. Picado has confirmed and extended the observa- tions of previous investigators. He has proved that the absorption of minerals from the water by the leaves is an habitual nutritive process and that these organs secrete a gummy matter (consisting of 77% bassorine and 27% arabine and diverse soluble substances), which has both an amylolytic and a proteolytic action on the organic detritus and thus renders its soluble portions assimilable by the plant. The insolu- ble refuse forms a kind of peat, which is free from proteids and starches and contains almost no traces of salts. Hence the purity of the water in the reservoirs and the absence of decomposition in the refuse as long as it remains in contact with the living leaves. The terrarium, which is formed by the failure of the old peripheral leaves to form acequate reservoirs, may therefore be said to consist of peat. The formation of this substance in the Bromeliads is compared by Picado with that of our northern bog-peat, which, unlike humus, is formed only under water that is constantly being renewed, "The climate, in which these 136 bulletin: museum of comparative zoology plants (the epiphytic Bromeliacese) grow, being very mild and the water in their tanks being very pure, since all its soluble contents are slowly and constantly diminished by absorption, the decomposition of the detritus occurs under conditions closely analogous to those that lead to the formation of peat-bogs." The Bromeliacea? of the type here discussed flourish most luxuriantly where they are fully exposed to the sun-light on the high branches of trees and where they would seem also to be most advantageously situated for securing their meteoric water and wind-blown detritus. But these conditions are rather unfavorable for ants, since as a rule they can find nesting sites only under the dry roots of the plants or in the terrarium. For this reason most of the water-bearing Bromeliads are avoided by the ants. There are certain species of Tillandsias, how- ever, which afford them much more favorable quarters. Since Picado has very little to say about these plants, we may turn to Schimper who was led to study them closely, because he found them constituting the great bulk of the epiphytic flora in the West Indies, where he first in- vestigated the ecology of tropical plants (1884). His earlier account is reproduced in his paper of 1888 from which I quote: "In Tillandsia flexuosa, which inhabits very dry, sunny situations, the tips of the leaves are brought together over the water-reservoir and spirally twisted around one another, so that the latter is entirely concealed from the direct sun-light but accessible to the rain and dew by means of the long slender canals. But the most complete protective arrange- ments are found in Tillandsia bulbosa, which also grows in sunny situations and is represented on our Plate IV. The leaves of Tillandsia bulbosa are spoon-shaped at their ensheathing bases, whereas the blade is cylindrical and either trough-like, with a narrow slit, or tubular, with the leaf-margins closely approximated or overlapping each other. The blade is always more or less strongly retroflected and twisted around its axis. The sheaths form an onion-like bulb which is nearly everywhere compactly closed and since they are strongly and con- vexly spoon-shaped and applied to one another only at their margins, contain large cavities continued above into the tubular leaf-blade and provided with only a very small orifice opening to the outside at the junction of the sheath and blade. The peripheral half of the tubular blade consists of chlorophyll-containing parenchyma and a very thin layer of aquiferous tissue; the inner side, on the contrary, is quite colorless and carpeted with exceedingly numerous, very large scales, which are sunk into a dense layer of aquiferous tissue. While young, the sheath, so far as it is covered by the other leaves, is devoid of wheeler: neotropical ant-plants and their ants 137 chlorophyll, thin and invested on both surfaces with scales which sur- pass in dimensions those of most of the other species and are so densely crowded that the epidermis is reduced to narrow strands. The plant entirely lacks the very strong negative geotropism characteristic of the rosettes of the epiphytic Bromeliacese. It occurs sometimes on the upper, sometimes on the lower side of the branches, or on perpendicu- lar trunks, and grows in an erect horizontal or inverted position, with- out ever exhibiting a trace of geotropic curvature. The bulbs always contain water in their inner cavities, besides earthy materials and small dead insects, whereas the outermost cavities are free from such substances and harbor ants. That the contained water does not fall out, even in the inverted position, requires no explanation, since each chamber, except for its small upper orifice, is tightly closed on all sides. How the water manages to gain entrance, however, calls for brief explanation. If drops of water are allowed to fall on the margins of the leaf-blades, no matter whether they overlap or are merely ap- proximated, the liquid is greedily sucked in by capillarity. The same occurs at the margins of the sheaths and at the narrow orifice at the base of the blade. By such means the cavities may be filled in a short time, and this occurs in nature in the presence of rain or dew. It should be emphasized, in case this experiment is repeated, that the first drop is less quickly imbided, if the plant happens to have remained un- moistened for some time. The outer leaves are, in fact, usually not easily wetted and take up only a small amount of water. Not only does water enter the wetted bulbs, even when they are inverted, but they may, in any position, as shown in our figure, imbibe water and eventually conduct it into their reservoirs. The earthy materials, which are always present in the water, are derived from the small amounts of solids that are washed off by the rain from the leaves and branches of the host tree. The plant probably secures its nitrogen also from the cadavers of the ants, which are not content to remain in the peri- pheral cavities, but also, as we have found, make fatal incursions into the water-containing chambers. The narrow orifice at the base of the leaf-blade serves the ants as an entrance." Schimper thus seems to have been the first to notice the regular nidification of ants in Tillandsias. Since 1901, when I recorded the occurrence of several species of these plants in the neighborhood of Cuernavaca, Mexico, I have been able to observe the same association on numerous occasions in several of the countries surrounding the Gulf and Caribbean. The insects live only in the species of Tillandsia that have the leaf-bases more or less spoon-shaped and compactly 138 bulletin: museum of comparative zoology overlapping. The species concerned are those designated in the litera- ture as T. utriculata Linn., fasciculata Swarts, balbisiana Schultes, Benthamiana Klobsch, aloifolia Hooker and flexuosa. Unfortunately I failed to collect specimens of the various Tillandsias in which I found Formicidse so that I am in most cases uncertain of the precise identi- fication of the plants. The ants enter and leave the Tillandsias either through the small preformed openings near the tips of the expanded leaf-bases, as Schimper observed, or as I have observed, through larger openings which they gnaw in the leaf-bases. Since such openings are made not only in the outermost but also in the enclosed leaves, the ants are pro- vided with a number of convenient intercommunicating chambers. Incipient colonies of larger species and single adult colonies of minute species often confine themselves to the space between a single leaf- base and those which it covers, so that not infrequently several dif- ferent species may occupy as many different chambers in the same plant and live as near neighbors, or in a kind of paroecism or parabiosis. The ants rarely enter the wet innermost portion of the plant, and I am inclined to believe that the openings which they gnaw prevent any deleterious retention of water in their chambers by serving to draw it away. More careful observations in the field, however, are required to substantiate this supposition. Owing to the fact that Picado did not bestow special attention on the Tillandsias, the Hymenoptera in his conspectus of the known Bromeliaceous fauna, comprise only the two species of ants (Odon- tomachus hastatus&ndApterostigma calverti) observed byCalvert in some of the genera of larger Costa Rican Bromeliads. The following list of ants shows that they really constitute a considerable portion of the Bromeliad biocoenose as a whole. I include several forms recorded by Luederwaldt as occurring among or under the roots of epiphytes. Though the latter may not have been Bromeliacese, the ants mentioned very probably live occasionally among the roots of these plants. It is obviously impossible to draw a hard and fast line between such nesting sites and the ant-gardens. (1) Ectatomma (Gnamptogenys) annulatum Mayr. Among roots of epiphytes with Phcidolc angusta Forel as neighbors. Brazil (H. Luederwaldt). (2) Holcoponcra striatula Mayr. Nesting between leaves of Brom- eliacese. Brazil (H. Luederwaldt). (3) Neoponera crenata Roger. In dried fruits of Bromclia fastuosa Lindh. and in B. cpiphytica. Brazil (Luederwaldt). wheeler: neotropical ant-plants and their ants 139 (4) Ncoponcra crenata var. vicesta Mayr. In the same plants. Brazil (Luederwaldt). (5) Neoponera villosa Fabr. Nesting under Bromelia epiphytica. Brazil (Luederwaldt). (6) Ponera distinguenda Emery. Nesting under roots of epiphytes. Brazil (Luederwaldt). (7) Ponera foeda Forel var. saroltoe Forel. Nesting under roots of epiphytes. Brazil (Luederwaldt). (8) Anochctus altisquamis Mayr. Among roots of Bromeliacere. Brazil (Luederwaldt). (9) Odontomachus hastatus Fabr. Between leaves of Bromeliacere and other epiphytes. Costa Rica (P. P. Calvert) ; Brazil (Luederwaldt). (10) Pscudomyrma elongata Mayr. In Tillandsias. Florida (Wheeler). (11) Pscudomyrma gebelli Forel. In Tillandsia aloifolia Hooker. Panama (Wheeler). (12) Pscudomyrma gracilis Fabr. subsp. mexicana Roger. In Tillandsia Benthamiana Klotsch. Mexico (Wheeler). (13) Pscudomyrma sericea Mayr var. timeni Forel. Under epiphytes. Brazil (Luederwaldt). (14) Phcidole anastasii Emery var. sospes Forel. Among roots of ephiphytes. Brazil (Luederwaldt). (15) Phcidole angusta Forel. Among roots of epiphytes with Ecta- tomma (Gnamptogenys) annulatum as neighbors, Brazil (Luederwaldt). (16) Pheidole emeryi Mayr. Among roots of epiphytes. Brazil (Luederwaldt). (17) Pheidole punctatissima Mayr. In Bromeliacese and in green spathes of Dicffenbachia ocrstedi. Costa Rica (P. Biolley). (18) Crematogaster acuta Fabr. In Tillandsia aloifolia. Panama (Wheeler). (19) Crematogaster (Orthocrema) arcuata Forel var. aruga Forel. In Tillandsia aloifolia. Panama (Wheeler). (20) Crematogaster (Orthocrema) brevispinosa Mayr. In tufts of Bromeliacese. (21) Crematogaster (Orthocrema) brevispinosa var. minutior Forel. In Tillandsia Benthamiana. Mexico (Wheeler). (22) Crematogaster (Orthocrema) brevispinosa var. tumulifera Forel. In Tillandsia aloifolia. Panama (Wheeler). (23) Crematogaster (Orthocrema) distans Mayr. In Tillandsias. Guatemala and Costa Rica (Wheeler). 140 bulletin: museum of comparative zoology (24) Crematogaster (Orthocrema) limata F. Smith subsp. parabiotica Forel. In Tillandsia aloi folia. Panama (Wheeler). (25) Crematogaster (Orthocrema) montezumia F. Smith var. sulcata Mayr. In ant-gardens among Tillandsias. Brazil (E. Wasmann). (26) Crematogastcr (Orthocrema) sculpturata Pergande. In Tilland- sias. Guatemala (Wheeler). (27) Crematogaster (Orthocrema) steinheili Forel. In Tillandsias. Bahamas (Wheeler). (28) Crematogaster (Orthocrema) virgula Forel. In Tillandsias. Porto Rico (Wheeler). (29) Crematogaster (Acroccelia) lucayana Wheeler. In Tillandsias. Bahamas (Wheeler). (30) Crematogaster (Acrocalia) lucayana subsp. etiolata Wheeler. In Tillandsias. Bahamas (Wheeler). (31) Monomorium carbonarium F. Smith subsp. ebeninum Forel. In Tillandsias. Bahamas (Wheeler). (32) Monomorium floricola Jerdon. In Tillandsias. Florida, Bahamas, Cuba, Porto Rico (Wheeler). (33) Xenomyrmex stolli Forel subsp. fioridanus Emery var. lucayanus Wheeler. In Tillandsias. Bahamas (Wheeler). (34) Solenopsis corticalis Forel subsp. amazonensis Forel. In Tillandsias (Pseudocatopsis sp.). Peru (E. Ule). (35) Solenopsis decipiens Emery subsp. adjecta Emery. Nesting under roots of epiphytes. Brazil (Luederwaldt). (36) Macromischa petiolata Forel. In Tillandsia Benthamiana. Mexico (Wheeler). (37) Leptothorax (Goniothorax) echinatinodis Forel subsp. dalmasi Forel. In Tillandsias. Costa Rica (Wheeler). (38) Cryptoccrus aztecus Forel. In Tillandsia Benthamiana. Mexico (Wheeler).^ (39) Cryptocerus scutulatus F. Smith. In Tillandsias. Costa Rica (Wheeler). (40) Cryptocerus loheeleri Forel. In Tillandsia Benthamiana. Mexico (Wheeler). (41) Cryptocerus (Cyathocephalus) varians F. Smith. In Tillandsias. Florida (Wheeler). (42) Aptcrostigma calverti Wheeler. Nesting in Bromeliacese and making fungus-gardens of insect excrement. Costa Rica (P. P. Cal- vert) . (43) Cyphomyrmex auritus Mayr. Nesting among roots of epiphytes. Brazil (Luederwaldt). wheeler: neotropical ant-plants and their ants 141 (44) Dolichoderus (Hypoclinea) championi Forel subsp. trinidadensis Forel var. tseniatus Forel. In Tillandsia aloifolia. Panama (Wheeler). (45) Dolichoderus (Hypoclinea) lutosus F. Smith. In Tillandsias. Costa Rica (Wheeler). (46) Dolichoderus (Monads) bispinosus Olivier. In Tillandsia aloi folia. Panama (Wheeler). (47) Iridomyrmex iniquus Mayr var. nigellus Emery. In Tillandsias. Guatemala and Costa Rica (Wheeler). (48) Iridomyrmex sordescens Wheeler. In Tillandsias. Costa Rica (Wheeler). (49) Azteca traili Emery subsp. tillandsiarum Wheeler. In Tilland- sias. British Guiana (Wheeler). (50) Azetca vehx Forel. In Tillandsias. Costa Rica (Wheeler). (51) Tapinoma littorale Wheeler. In Tillandsias. Florida and Bahamas (Wheeler). (52) Tapinoma littorale var. cubaensis Wheeler. In Tillandsias. Cuba (Wheeler). (53) Myrmelaehista, ambigua Forel subsp. ramidorum Wheeler. In Tillandsias. Costa Rica (Wheeler). (54) Myrmelaehista (Decamera) zeledoni Emery. In Tillandsias. Costa Rica (Wheeler). (55) Paratrechina longicornis Latr. In Tillandsia paraensis Mez. Brazil (E. Ule). (56) Paratrechina (Nylandcria) fulva Mayr. Nesting among leaves of Bromeliacea?. Brazil (Luederwaldt). (57) Camponotus (Tanaemyrmex) conspicuus F. Smith subsp. zonatus Emery. In Tillandsias. Costa Rica (Wheeler). (58) Camponotus (Tanaemyrmex) ramulorum Wheeler. In Tilland- sias. Bahamas (Wheeler). (59) Camponotus ( Tanaemyrmex) ramidorum var. marcidus Wheeler. In Tillandsias. Bahamas (Wheeler). (60) Camponotus (Myrmothrix) cingulatus Mayr. Among Bromel- iacese. Brazil (Luederwaldt). (61) Camponotus (Myrmothrix) abdominalis Fabr. var. costaricensis Forel. In Tillandsias. Costa Rica (Wheeler). (62) Camponotus (Myrmothrix) abdominalis subsp. mediopallidus Forel. In Tillandsia Benthamiana, Mexico (Wheeler). (63) Camponotus (Myrmobrachys) planatus Roger. In Tillandsias. Cuba (Wheeler). (64) Camponotus (Myrmobrachys) planatus var. continentis Forel. In Tillandsias. Florida (Wheeler). 142 bulletin: museum of comparative zoology (65) Camponotus (Myrmophoenus) fastigiatus Roger subsp. schmalzi Emery. Nesting under epiphytic Bromeliaeese. Brazil (Luederwaldt). (66) Camponotus (Myrmocladoecus) bidens Mayr. In Tillandsias. Costa Rica (Wheeler). (67) Camponotus (Myrmocladoecus) rectangularis Emery subsp. rubroniger Forel. In Tillandsia Bcnthamiana. Mexico (Wheeler). (68) Camponotus (Hypcrcolobopsis) paradoxus Mayr subsp. janitor Forel. Among leaves of Bromeliacea?. Brazil (H. von Ihering). Many of the ants in this list live also in hollow twigs or in other available plant-cavities. One species, Apterostigma calverti, is of un- usual interest, because it belongs to the fungus-growing Attini, which regularly nest in the ground, under stones or in and under rotten logs, and is therefore exceptional in having become arboreal and in con- structing its gardens in the terraria of large Bromeliads with the excre- ment of the beetles or caterpillars that feed on their foliage. Cyphomyr- mex auritus is another fungus-growing ant which is recorded by Luederwaldt as nesting and making its gardens among the roots of epiphytes. It may, therefore, occasionally live among Bromeliads. I am inclined to believe that yet another Attine ant, Cyphomyrmex salvini Forel, may eventually be found to have similar habits. In Panama I have taken it repeatedly under the bases of palm-petioles several feet above the ground. It might, therefore, nest about the roots of Bromeliads and other epiphytes. Its gardens consist of the collected excrement of small insects and are covered with a peculiar fungus very much like that cultivated by C. rimosus Spinola and its various subspecies (see Wheeler, 1907, p. 771, PI. 50, Fig. 29). The colonies of ants nesting in Tillandsias are singularly free from parasites or myrmecophiles. The only ant-guest which I have seen in these plants is a flat, broadly elliptical Microdon puparium in a colony of Pscudomyrma gracilis subsp. mexicana, taken many years ago at Cuernavaca, Mexico. The adult larva of this insect is figured in my paper of 1901. The following table includes a list of the number of species of bromeliadicolous animals cited by Picado and the ants above enumer- ated: wheeler: neotropical ant-plants and their ants 143 Rotifera 1 Thysanoptera 1 Planarians 5 Dermaptera 28 Oligochaeta 8 , Plecoptera 1 Hirudinea 3 Odonata 1 Gastropoda 4 Hemiptera 8 Crustacea 9 Coleoptera 36 Onychophora 2 Lepidoptera 3 Myriopoda 16 Diptera 88 Arachnida 29 Hymenoptera (Formicidae). . . 66 Thysanura 1 Batrachia 6 Orthoptera 29 Total 342 This list represents, of course, only a small fraction of the total bromeliadicolous fauna, which has nowhere been exhaustively studied. Throughout great regions of Brazil, Eastern Peru and the Guianas no systematic search has been made for the animal tenants of the luxuri- ous epiphytic flora. The majority of the recorded species (261) are insects, but whole groups of animals, such as the Infusoria and Nema- todes, have received no attention. If we include the Bacteria, fungi and alga? which must be associated with the plants and their tenants the total Bromeliad bioccenosis would probably be very extensive. Picado mentions Saprolegniacese on the aquatic insect larvae and Werckle states that the flowers of certain Tillandsias are often greatly injured by smuts. There are, as we have seen, fungi in the gardens of Aptcrostigma calverti and other species no doubt invade the peaty remains of the terraria. The fauna and flora of the epiphytic vegetation may be suggested as very promising subjects for intensive investiga- tion in some of the laboratories that have been recently established in the American tropics. 1 ■Professor Wheeler intended to expand the Chapter dealing with the Bromeliaceae. Among other recent papers which he wanted to review are three important contributions by Miss Skwarra (1930, 1934a, 1934e) on ant plants and bromeliads of Mexico. [J. Bequaert]. 144 bulletin: museum of comparative zoology REFERENCES 1 Alfaro, A. 1935. Investigaciones cientificas. (San Jose de Costa Rica), 219 pp. (Cecropia and Acacia, pp. 195-203). Aso, K. 1910. Konnen Bromeliaceen durch die Schuppen der Blatter Salze aufnehmen? Flora, 100, pp. 447-450. AlJBLET, J. B. 1775. Histoire des plantes de la Guyane Francaise. (Paris), 4 vols., xxxii + 976 + 52 + 160 pp., 392 pis. Bailey, I. W. 1922a. The Anatomy of certain plants from the Belgian Congo, with special reference to myrmecophytism. Bull. Amer. Mus. Nat. Hist., 45, pp. 585-621, 16 pis. 1922b. Notes on Neotropical ant-plants. I. Cecropia angulata sp. nov. Bot. Gazette, 74, pp. 369-391. 1923. Notes on Neotropical ant-plants. II. Tachigalia paniculata Aubl. Bot. Gazette, 75, pp. 27-41, 2 pis. 1924. Notes on Neotropical ant-plants. III. Cordia nodosa Lam. Bot. Gazette, 77, pp. 39-19, 2 pis. Barber, H. S. 1928. A new Bolivian silvanid beetle from the myrmecodomatia of Cordia. Psyche, 35, pp. 167-168. Beccari, O. 1884-1886. Piante ospitatrici ossia formicarie della Malesia e della Papuasia. Malesia, 2, pp. 1-340, 65 pis. Belt, T. 1874. The naturalist in Nicaragua. (London), xvi + 403 pp. Bentham, G. 1870-1876. Leguminosae. In de Martius and Eichler, Flora brasiliensis. (Munich), vol. 15, pt. 2. Bequaert, J. 1922. Ants in their diverse relations to the plant world. Bull. Amer. Mus. Nat. Hist., 45, pp. 333-583, 4 Pis. Betjrling, P. J. 1854. Primitiae Florae portobellensis sive enumeratio plantarum vas- cularum quas juxta oppidum Portobello in isthmo panamensi Americae centralis mense Aprili anno 1826 legit Joh. Em. Billberg. Svensk. Vet. Akad. Handl., 105-148. 'Prepared by Dr. Joseph Bequaeit. wheeler: neotropical ant-plants and their ants 145 BOHEMAN, C. H. 1853. Monographia Cassidarum. Vol. 3, (Holmiae). BOLDINGH, H. 1914. The flora of Curasao, Aruba and Bonaire (Leiden). Borgmeier, T. 1923. Beitrag zur Biologie der Feuerameise und ihrer Gaste. Zeitschr. Deutsch. Ver. Wiss. Kunst, Sao Paulo, 3, pp. 1-9. Boulger, G. S. 1908. Wood. A manual of the natural history and industrial applica- tions of the timbers of commerce. (London). Breynius, J. 1739. Prodromi fasciculi rariorum plantarum primus et secundus. (Gedani), 108 + 54 pp., 32 pis. (Acacia, pp. 36-38). Brues, C. T. 1922. Conoaxima, a new genus of the Hymenopterous family Eury- tomidae, with a description of the larva and pupa. Psyche, 29, pp. 153-158. BUSCALIONI, L. AND HuBER, J. 1900. Eine neue Theorie der Ameisenpflanzen. Beihefte Bot. Zentralbl., 9, pt. 2, pp. 85-88 Calvert, P. P. 1910a. A plant-dwelling Odonate larva. Ent. News, 21, pp. 264 and 365-366. 1910b. Zoological researches in Costa Rica. Old Penn, 9, pp. 165-170. 1911. Studies on Costa Rican Odonata, II-III. Ent. News, 22, pp. 402-411, 449-460, 3 Pis. Calvert, A. S. and Calvert, P. P. 1917. A year of Costa Rican natural history. (New York), xix + 577 pp. Cedervall, E. V. 1884. Anatomiskt-fysiologiska Undersokningar ofver Bladet hos Brome- liaceerna. Goteborgs Kongl. Vet. Handl., 19, pp. 1-55, 5 Pis. Champion, G. C. 1893-1894, Cassididae. In Biologia Centrali-Americana. Coleoptera, vol. 6, Pt. 2. Chodat, R. 1920. Revision critique des especes de Cordia appartenant a la section Gerascanthus (Cham.) et de quelques especes du meme genre. Bull. Soc. Bot. Geneve, (2) 12, pp. 209-218. Chodat, R. and Carisso, L. 1920a. Une nouvelle theorie de la myrmecophilie. C. R. Seances Soc. Phys. Hist. Nat. Geneve, 37, pp. 9-12. 146 bulletin: museum of comparative zoology 1920b. La vegetation du Paraguay. La myrmecophilie des Cordias de la section Gerascanthus. Bull. Soc. Bot. Geneve, (2) 12, pp. 172-200. Chodat, R. and Vischer, W. 1920. La vegetation du Paraguay. Borraginacees. Bull. Soc. Bot. Geneve, (2) 12, pp. 157-171. Cobo, P. Bernabe 1653. Historia del Nuevo Mundo. Vol. 2, Lib. 6, Cap. CXXIX, p. 126 (Palo santo). COCKERELL, T. D. A. 1928. Bees collected by Dr. W. M. Wheeler at the flowers of Triplaris. Psyche, 35, pp. 170-172. COMMELYN, J. 1697-1701. Rariorum plantarum Horti Medici Amstelodamensis des- criptio (Amsterdam). Vol. 1, 220 pp., 112 pis.; Vol. 2, 224 + 112 pp. Dammer, U. 1893. Polygonaceae. In Engler and Prantl, Die Naturlichen Pflanzen- familien, (Leipzig), Vol. 3, Pt. 1, Abth. a, pp. 1-36. Darwin, F. 1877. On the glandular bodies on Acacia sphaerocephala and Cecropia peltata serving as food bodies. Jl. Linn. Soc. London, Bot., 15, pp. 398^09, 1 PI. Delpino, F. 1886-1889. Funzione mirmecofila nel regno vegetabile. Prodromo d'una monografia delle piante formicarie. Mem. Ace. Bologna, (4) 7, pp. 215-323 (1886); (4) 8. pp. 601-659 (1887); (4) 10, pp. 115- 147 (1889). DONISTHORPE, H. S. J. K. 1912. Myrmecophilous notes for 1911. Ent. Record, 24, pp. 4-10, 34-40. 1923. Myrmecophilous notes for 1922. Ent. Record, 35, pp. 1-9. Ducke, A. 1910. Revision des guepes sociales polygames d'Amerique. Ann. Mus. Nat. Hungar., 8, pp. 449-544. Emery, C. 1892. Hormigas de Costa Rica, que viven en las Acacias. Anal. Mus. Nac. San Jose, (1888-1889), pp. 65-67. 1893. Studio monografico sul genere Azteca Forel. Mem. R. Accad. Sci. Inst. Bologna, (5) 3, pp. 319-352, 2 Pis. w heeler: neotropical ant-plants and their ants 147 1896. Alcune forme nuove del genere Azteca For. e note biologiche Boll. Mus. Zool. Anat. Comp. Torino, 11, No. 230, pp. 1-7. 1912. Le piante formicarie. Scientia, 12, pp. 48-62. Fiebrig, K. 1909. Cecropia peltata und ihr Verhaltnis zu Azteca alfari, zu Aita sexdens und anderen Insekten, mit einer Xotiz liber Ameisen- Dornen bei Acacia cavenia. Biol. Centralbl., 29, pp. 1-16, 33-55, 65-77, 5 Pis. FOREL, A. 1899-1900. Formicidae. In Biologia Centrali- Americana. Hymen- optera, vol. 3. 1904. In und mit Pflanzen lebende Ameisen aus dem Amazonas-Gebiet und aus Peru. Zool. Jahrb. Syst., 20, pp. 677-707. 1905. Miscellanea myrmecologiques. Ann. Soc. Ent. Belgique, 49, pp. 155-160. 1906. Fourmis neotropiques nouvelles ou peu connues. Ann. Soc. Ent. Belgique, 50, pp. 225-249. 1920. Fourmis trouvees dans les galles de Cordia et d'Agonandra, etc. Bull. Soc. Bot. Geneve, 12, 201-208. GtlRKE, M. 1897. Borraginaceae. In Engler and Prantl, Die Natiirlichen Pflanzen- familien, Vol. 4, pt. 3, Abt. a, pp. 71-131. Harms, H. 1906. Leguminosae (in Ule, Beitrage zur Flora der Hyalea). Verh. Bot. Ver. Prov. Brandenburg, 48, pp. 164-165. Hemsley, W. B. 1882-1886. Biologia Centrali-Americana, Botany, vol. 3. (Triplaris, p. 38). Hernandez, F. 1651. Rerum medicarum Novae Hispaniae thesaurus seu plantarum, animalium et mineralium Mexicanorum historia. (Rome), xiv + 950 + 22 + 90+6 pp. HOHENKERK, L. S. 1918. Botanical identifications of British Guiana trees and plants. Jl. Board Agric. Brit. Guiana, 11, pp. 98-106, 178-185. HUBER, J. 1909. Materiales para a flora amazonica. VII. Plantae Duckeanae austro-guyanenses. Bol. Mus. Goeldi, 5, (1908), pp. 387-388. 1910. Novitates florae amazoniae (I). Bol. Mus. Goeldi, 6 (1909), pp. 60-90. 148 bulletin: museum op comparative zoology Huth, E. 1887. Myrmecophile und myrmecophobe Pflanzen. (Berlin), 27 pp., 2 Pis. Ihering, H. von 1891. Die Wechselbeziehungen zwischen Pflanzen und Ameisen in den Tropen. Das Ausland, 1891 : 474-477. 1907. Die Cecropien und ihre Schutzameisen. Engler's Bot. Jahrb., 39, pp. 666-714, 5 Pis. Jacquin, N. J. 1763. Selectarum stirpium americanarum historia. (Vienna), vii + 284 pp., 183 Pis. Johnston, I. M. 1924. Taxonomic records concerning American spermatophytes. 2. New or otherwise noteworthy plants. Contrib. Gray Herb. Harvard Univ., N. S. 70, pp. 69-87. Knab, F. 1912. A new species of Anisopidae (Rhyphidae) from tropical America. Proc. Biol. Soc. Washington, 25, pp. 111-112. 1913a. Larvae of Cyphonidae in Bromeliaceae. Ent. Mo. Mag., (2) 24, pp. 54-55. 1913b. A new bromeliocolous Megarhinus. Insec. Inscit. Menstr., 1, pp. 35-36. Koelsch, K. A. 1908. Die Theorie der Ameisenpflanzen — Ein Irrtum der Biologie. Beil. z. Allgem. Zeitg. Miinchen, No. 8: 59-61. (Review in 1910, Zeitschr. Wiss. Insektenbiol., 6, p. 36). Lkng, C. W. 1920. Catalogue of the Coleoptera of America, north of Mexico. (Mount Vernon, N. Y.). LlNNE, C. VON 1737. Hortus Cliffortianus. (Amsterdam), x + iv + 501 + 16 + 36 pp. 1 PI. LUEDERWALDT, H. 1926. Observacoes biologicas sobre formigas brasileiras, especialmente do Estado de Sao Paulo. Rev. Mus. Paulista, 14, pp. 1-118, 5 Pis. Mann, W. M. 1928. A new Microdon from Panama. Psyche, 35, pp. 168-170. wheeler: neotropical ant-plants and their ants 149 Marcgravius de Liebstad, G. 1648. Historiae rerum naturalium Brasiliae libri octo. (Amsterdam), viii + 300 pp. Maza, M. G. de la and Roig, J. T. 1916. Flora de Cuba. Bol. 22, Estac. Agronomica Santiago de las Vegas. Meinert, F. 1892. Traek of Insektlivet i Venezuela. Entom. Meddelelser, 3, pp. 125-144. Meisner, K. F. 1856. Polygoneae. In De Candolle, Prodromus Systematis Naturalis Regni Vegetabilis, Vol. 14: 171-178. Men£gaux, A. 1909. Contribution a l'etude des Edent£s actuels, Famille des Brady- podides. Arch. Zool. Exp. Gen., (5) 1, pp. 277-344, 4 Pis. Menozzi, C. 1927. Formiche raccolti dal Sig. H. Schmidt nei dintorni di San Jose de Costa Rica. Entom. Mitt., Berlin, 16, pp. 266-277, 336-345. 1930. Formiche della Somalia italiana meridionali. Mem. Soc. Ent. Italiana, 9, pp. 76-130, 3 Pis. Mez, C. 1890. Morphologische und anatomische Studien iiber die Gruppe der Cordieae. Engler's Bot. Jahrb., 12, pp. 526-588, 2 Pis. 1904. Physiologische Bromeliaceen-Studien. Jahrb. Wiss. Bot., 40, pp. 157-229. Miquel, F. A. W. 1850. Stirpes surinamenses selectae. Natuurk. Verh. Bataafsch. Maatsch. Wetensch., (2) 7, (1851), 7 + 234 pp., 65 Pis. Moebius, M. 1925. Versuch zur Erklarung der Ameisenpflanzen. Flora, (N. F.) 118-119, pp. 393-398. Morrison, H. 1922. On some trophobiotic Coccidae from British Guiana. Psyche, 29, pp. 132-152, 2 Pis. MORTEO, E. 1904. Sopra due piante formicarie. Malpighia, 18, pp. 504-511, 2 Pis. Muller, Fritz 1876. Ueber das Haarkissen am Blattstiel der Imbauba (Cecropia), das Gemiisebeet der Imbauba-Ameise. Jen. Zeitschr. Naturw., 10. pp. 281-286. 150 bulletin: museum of comparative zoology 1879. Wasserthiere in den Wipfeln des Waldes. Kosmos, Leipzig, 4, pp. 390-392. 1880. Wasserthiere im Baumwipf eln . Elpidium bromeliarum. Kosmos, Leipzig, 16, pp. 386-388. 1880. Die Imbauba und ihre Beschiitzer. Kosmos, Leipzig, 18, pp. 109-116. 1883. (On Cecropia). Blumenauer Zeitung, January. Paoli, G. 1929. Strane abitazioni di una formica su acacie della Somalia. Riv. Colonie Italiane, 3, pp. 474-485, 4 Pis. 1930. Contribute alio studio dei rapporti fra le acaeie e la formiche. Mem. Soc. Ent. Italiana, 9, pp. 131-195, 7 Pis. PlCADO, C. 1911. Les Bromeliaeees epiphytes eomme milieu biologique. C. R. Acad. Sci. Paris, 153, p. 960. 1912a. Sur la nutrition chez les Bromeliaeees epiphytes. C. R. Acad. Sci. Paris, 154, p. 607. 1912b. Les mares aeriennes de la foret vierge americaine. Les Brom- eliaeees. Biologica, 2, pp. 110-115. 1913. Les Bromeliaeees epiphytes considerees eomme milieu biologique. Bull. Scientif. France Belgique, 47, pp. 215-360, 19 Pis. Piso, G. 1658. Historia naturalis Brasiliae. (Antwerp). PlTTIER, H. 1908. Ensaya sobre las plantas usuales de Costa Rica. (Washington, D. C). Plukenett, L. 1696. Almagestum botanicum. (London), 402 pp. 1720. Opera omnia botanica. 6 vols. Pulle, A. 1906. An enumeration of the vascular plants known from Surinam, together with their distribution and synonymy. (Leiden). Ray, J. 1686-1704. Historia plantarum. (London), 3 Vols. {Cecropia, Vol. 3, p. 1373). Rettig, E. 1904. Ameisenpflanzen-Pflanzenameisen. Beih. z. Bot. Centralbl., 17, pp. 89-122. RODWAY, J. 1911. In the Guyana forest. Studies of nature in relation to the struggle for life. (London) 2nd Ed., 326 pp. wheeler: neotropical ant-plants and their ants 151 Ross, H. 1909. Pflanzen und Ameisen im tropischen Mexiko. Naturwiss. Wochenschr., 8, pp. 822-830. Ruiz, H. and Pavon, J. 1799. Flora peruviana et chilensis. (Madrid), Vol. 2. {Cordia, Vol. 2: 47; PL 184). Safford, W. H. 1910. Bull-horn acacias in botanical literature, with a description of two new species. Science, (N. S.) 31, pp. 676-677. 1914. Acacia cornigera and its allies. Jl. Washington (D. C.) Ac. ScL, 4, pp. 356-368. 1915. New or imperfectly known species of bull-horn acacias. Jl. Washington (D. C.) Ac. ScL, 5, pp. 355-360. 1922. Ant acacias and acacia ants of Mexico and Central America- Smithson. Rept. for 1921: 381-394, 15 Pis. Saldanha da Gama, Jose de 1874. Notes sur quelques arbres employes dans l'industrie bresilienne. Ann. Sci. Nat., Botan., (5) 19, pp. 210-218. SCHENCK, H. 1913. Acaciae myrmecophilae novae. Fedde's Repertorium, 12, p. 370. 1914. Die myrmekophilen Acan'a-Arten. Engler's Bot. Jahrb., 60, SuppL, pp. 449-487. SCHIMPER, A. F. W. 1884. L T eber Bau und Lebensweise der Epiphyten Westindiens. Botan. Centralbl., 17, pp. 192-195, 223-227, 253-258, 284-294, 319-326, 350-359, 381-389, 2 Pis. 1888a. Die Wechselbeziehungen zwischen Pflanzen und Ameisen im tropischen Amerika. (Jena), 95 pp., 3 Pis. 1888b. Die epiphytische Vegetation Amerikas. (Jena), 162 pp., 6 Pis. 1903. Plant geography upon a physiological basis. (Oxford), xxx + 839 pp. SCHOMBTJRGK, RlCHARD 1847-1848. Reisen in Britisch-Guiana in den Jahren 1840-1844. (Leip- zig), 3 Vols. SCHOMBTJRGK, ROBERT 1838. On the ant tree of Guiana (Triplaris americana). Ann. Nat. Hist., 1, pp. 264-267. Schumann, K. 1888. Einige neue Ameisenpflanzen. Jahrb. Wiss. Bot., 19, pp. 357- 421, 2 Pis. 152 bulletin: museum of comparative zoology 1889. Ueber Ameisenpflanzen. Samml. Gemeinverst. Wiss. Vortrage (Hamburg), 38 pp., 1 PI. 1891. Rubiaceae. In Engler and Prantl, Die Naturlichen Pflanzen- familien, Vol. 4, pt. 4: 1-156. Schwarz, E. A. 1901. On the insect fauna of £he mistletoe. Proc. Ent. Soc. Washington, 4, pp. 392-394. 1917. Ants protecting Acacia trees in Central America. Proc. Ent. Soc. Washington, 18 (1916), p. 211. Scott, H. 1912. A contribution to the knowledge of the fauna of Bromeliaceae. Ann. Mag. Nat. Hist., (8) 10, pp. 424-431, 433-437. Seem ann, B. 1852-1857. The botany of the voyage of H.M.S. Herald under the command of Capt. Henry Kellett during the years 1845-51. (London), 6 + 483 pp., 98 Pis. Severiano da Fonseca, J. 1881. Viagem ad redor do Brazil. (Vol. 1:325). Skwarra, E. 1930. Ameisen und Ameisenpflanzen im Staate Veracruz (Mexiko). 4. Wandervers. Deutsch. Entom. Kiel: 160-170, 2 Pis. 1934a. Oekologische Studien iiber Ameisen und Ameisenpflanzen in Mexiko. (Konigsberg i. Pr.), 153 pp. 1934b. Oekologie der Lebensgemeinschaften mexikanischer Ameisen- pflanzen. Zeitschr. Morph. Oekel. Tiere, 29, pp. 306-373. Smith, F. 1862. Descriptions of new species of aculeate Hymenoptera, collected at Panama by R. W. Stretch, Esq., with a list of described species, and the various localities where they have previously occurred. Trans. Ent. Soc. London, (3) 1, pp. 29-44. Smith, J. Donnel 1894. Undescribed plants from Guatemala and other Central American republics, XIII. Botan. Gazette, 19, pp. 255-266. 1895. Undescribed plants from Guatemala and other Central American republics, XV. Botan. Gazette, 20, pp. 281-295. Snethlage, E. H. 1923. Neue Arten der Gattung Cecropia, nebst Beitragen zu ihrer Systematik. Notizbl. Bot. Gart. Mus. Berlin-Dahlem, 8, No. 75, pp. 357-369. Spix, J. von and Martius, C. von 1831. Reise in Brazilien in den Jahren 1817 bis 1820. (Vol. 3, pp. 1283- 1284, Melastomaceae). wheeler: neotropical ant-plants and their ants 153 Spruce, R. 1908. Notes of a botanist on the Amazon and Andes. (London), Vol. 1, lii + 518 pp.; Vol. 2, xii + 542 pp. Stager, R. 1917. Beitrag zur Kenntnis stengelbewohnender Ameisen in der Schweiz. Rev. Suisse Zool., 25, pp. 95-109. Standley, P. C. 1922. Trees and shrubs of Mexico (Fagaceae-Fabaceae). Contrib. U. S. Nat. Herbarium, 23, pp. 171-515. 1924. Trees and shrubs of Mexico (Passifloraceae-Scrophulariaceae)- Contrib. U. S. Nat. Herbarium, 23, pp. 849-1312. 1927. The flora of Barro Colorado Island, Panama. Smithson. Miscell. Coll., 78, No. 8, 32 pp. 1928. Flora of the Panama Canal Zone. Contrib. U. S. Nat. Herbarium, 27, pp. 416, 66 pis. Tidestrom, I. 1925. Flora of Utah and Nevada. Contrib. U. S. Nat. Herbarium, 26, pp. 665, 15 pis. Tulasne, L. R. 1844. Legumineuses arborescentes de l'Amerique du Sud. Arch. Mus. Hist. Nat. Paris, 4, pp. 65-196. Ule, E. 1897. Symbiose zwischen Asclepias curassavica und einem Schmetterling nebst Beitrag zu derjenigen zwischen Ameisen und Cecropia. Ber. Deutsch Bot. Ges., 15, pp. 385-387. 1900. Ueber weitere neue und interessante Bromeliaceen. Ber. Deutsch. Bot. Ges., 18, pp. 318-327, 1 PI. 1905. Wechselbeziehungen zwischen Ameisen und Pflanzen. Flora > 94, pp. 491-497. 1906a. Ameisenpflanzen. Engler's Bot. Jahrb., 37, pp. 335-352, 2 Pis. 1906b. Ameisenpflanzen des Amazonasgebietes. In Karsten und Schenck, Vegetationsbilder. Series 4, 14 pp., 6 Pis. 1907-1908. Die Pflanzenformationen des Amazonas-Gebietes. Pflan- zengeographische Ergebnisse meiner in den Jahren 1900-1903 unternommenen Reisen. Engler's Bot. Jahrb., 40 (1907), pp. 114-172; (1908), pp. 398-443, 8 Pis. Warburg, O. 1892. Ueber Ameisenpflanzen (Myrmekophyten). Biol. Centralbl., 12, pp. 129-142. 154 bulletin: museum of comparative zoology Warming, E. 1894. Om et Par af Myrer beboede Traeer. Vidensk. Meddel. Naturh. Foren. Kjobenhavn, (5) 6 (1893), pp. 173-187. Wasmann, E. 1915. Eine neue Pseudomyrma aus der Ochsendornakazie in Mexiko. Tijdschr. v. Entom., 58, pp. 296-325, 4 Pis. (Nachtrag, 58, pp. 125-131). Weddell, H. A. 1849. Additions a la flore de l'Amerique du Sud. Ann. Sci. Nat., Botan., (3) 13, pp. 40-113, 249-268. Werckle, C. 1909. La sub region fitogeografica costarricense. Soc. Nac. Agric. Costa Rica, San Jose. Wheeler, W. M. 1901a. Microdon larvae in Pseudomyrma nests. Psyche, 9, pp. 222-224. 1901b. Notices biologiques sur les fourmis mexicaines. Ann. Soc. Ent. Belgique, 45, pp. 199-205. 1907. The fungus-growing ants of North America. Bull. Amer. Mus. Nat. Hist., 23, pp. 669-807, 5 Pis. 1908. The ants of Porto Rico and the Virgin Islands. Bull. Amer. Mus. Nat. Hist., 24, pp. 117-158, 2 Pis. 1910. Ants, their structure, development and behavior. (New York), xxv + 663 pp. 1913. Observations on the Central American Acacia ants. Trans. 2d. Intern. Entom. Congr. Oxford (1912), 2, pp. 109-139. 1921. A study of some social beetles in British Guiana and of their relations to the ant-plant Tachigalia. Zoologica, 3, pp. 35-183, 5 Pis. Wheeler, W. M. and Bailey, I. W. 1920. The feeding habits of Pseudomyrmine and other ants. Trans. Amer. Phil. Soc, (N. S.) 22, pp. 235-279, 5 Pis. Wheeler, W. M. and Bequaert, J. 1929. Amazonian myrmecophytes and their ants. Zoolog. Anzeiger (Wasmann-Festband), pp. 10-39. WlTTMACK, L. 1888. Bromeliaceae. In Engler and Prantl, Die Nattirlichen Pfknzen- familien, 2, Abt. 4, pp. 32-76 (Addenda: Nachtrag, 1897, pp. 61-69). Wolcott, G. N. 1923. Insectae Portoricensis. Jl. Dept. Agric. Porto Rico, 7, pp. 1-313. wheeler: neotropical ant-plants and their ants 155 Part II. NEOTROPICAL PLANT ANTS In the following pages I have endeavored to bring together the scattered information which has long been accumulating in our myrmecological literature concerning the Formicidae inhabiting living plants in the Neotropical Region, together with descriptions and records of the forms recently collected by Dr. W. M. Mann, Dr. J. C. Bradley, Prof. I. W. Bailey, Mr. H. O. Lang and myself. The citations of the literature are restricted to the actual records and do not cover mere taxonomic descriptions. These may be readily found by con- sulting the various fascicles by Professor Carlo Emery on the Formici- dae in the "Genera Insectorum". In some cases, no doubt, the collected records refer to the occurrence of ants in dead twigs and do not prop- erly belong in my list, since their authors sometimes fail to make the necessary distinction. Many species, however, which normally nest in dead twigs may occasionally inhabit cavities in living vegetable tissue. For the same reason I may have omitted a number of species which should have been included. Since, however, the list is presented merely as a convenient basis for future observations, these defects are not to be regarded too seriously. In its present form it gives a definite and suggestive picture of the known neotropical ants which have either already become exquisitely adapted and specialized for living in the various myrmecophytes that occur within their geographical range or are on the road to acquiring such an adaptation. Subfamily PONERINAE Genus Neoponera Emery Neoponera carinulata Roger British Guiana: Merume Mouth (H. O. Lang), nesting in the fistulose stems of Patima formicaria Johnston (Rubiaceae). Neoponera crenata Roger Wheeler, Zoologica 3, 1921, p. 138. British Guiana: Kartabo (Wheeler); in hollow petioles of Tachigalia paniculata Aubl. Panama: Barro Colorado Island, Gatun Lake, C. Z. (Wheeler), in cauline swelling of Cordia gerascanthus L. 156 bulletin: museum of comparative zoology Neoponera stipitum Forel Guatemala: Quirigua (Wheeler); in internode of a young Cecropia. British Guiana: Kartabo (Wheeler), nesting in a large branch of Cecropia sciadophylla var decurrens Snetl. Neoponera unidentata Mayr Wheeler, Zoologica 3, 1921, p. 138. British Guiana : Kartabo (Wheeler) ; in hollow petioles of Tachigalia paniculata Aubl. In the same locality I have also taken this ant on several occasions in the cauline swellings of Cordia nodosa L. Neoponera villosa F. Smith Mayr, Verh. Zool. bot. Ges. Wien 16, 1866, p. 720. Mexico: Vera Cruz at the foot of Orizaba; in the pseudo-bulbs of an orchid, Schomburgkia tibicinis. Genus Anochetus Mayr Anochetus (Stenomyrmex) emarginatus Fabr. Wheeler, Ecology 2, 1921, p. 96. British Guiana : Kartabo (Wheeler) ; in ant-gardens about the roots of epiphytes. This ant usually nests under bark or in the cavities of dead limbs. Genus Odontomachus Mayr Odontomachus affinis Guerin subsp. mayri Mann. , Mann, Psyche 19, 1912, p. 39 9 . Brazil: Madeira Mamore R.R., Matto Grosso (W.M. Mann). In ant gardens, living in parabiosis with Dolichoderus (Monads) debilis var. rufescens. 0. offinis usually nests in the ground. Its habits have been studied by Borgmeier. (Deutsch. Ver. Wiss. Kunst. 7, 1920, p. 31-38). Odontomachus hastatus Fabr. Calvert, A Year of Costa Rican Natural History, 1917, p. 231, fig. - Costa Rica: (P. P. Calvert), frequently nesting in Bromeliads. wheeler: neotropical ant-plants and their ants 157 Subfamily PSEUDOMYRMINAE Genus Pseudomyrma F. Smith PSEUDOMYRMA ACANTHOBIA Emery Emery, Zool. Jahrb. Abt. Syst. 9, 1896, p. 628, 9 9 o\ Paraguay: San Salvador (J. Bohls); in woody thorns of Acacia (cavenia). Var. fuscata Emery Emery, Zool. Jahrb. Abt. Syst. 9, 1896, p. 629, £ 9 d" . Paraguay: San Salvador (J. Bohls); in woody thorns of Acacia (probably cavenia). The other varieties and subspecies of acanthobia live by preference in dead twigs or the culms of grasses. Pseudomyrma alliodorae sp. nov. Plate 47, Fig. a Worker:. Length 2.5 — 2.8 mm. Head subrectangular, about one and two-thirds times as long as broad, as broad in front as behind, with feebly convex sides and very slightly sinuate posterior border. Eyes very large, elongate-elliptical, flat, more than half as long as the head, somewhat nearer the anterior than the posterior corners. Ocelli well-developed. Mandibles convex at the base, more flattened distally, with five well-developed teeth. Clypeus very short, laterally depressed, its anterior border projecting in the middle as a short, narrow lobe with straight edge and sharp corners. Frontal carinae represented by a short, convex, longitudinal ridge continuous with the clypeal lobe. Frontal groove absent. An- tennae short; the scapes scarcely attaining the middle of the head, rather slender, curved, about four times as long as broad; first funicu- lar joint one and one-half times as long as broad; remaining joints, except the last, transverse, nearly twice as broad as long. Thorax rather elongate, the pro- and mesonotum together equal to the epino- tum; the promesonotal and mesoepinotal sutures pronounced, the dorsal outline at the latter rather deeply and abruptly notched. Pro- notum longer than broad, slightly narrowed behind, bluntly submargi- nate on the sides; mesonotum rather flat, broader than long, its anterior border bluntly angular, its posterior border rounded. Epinotum nar- 158 bulletin: museum of comparative zoology rowed behind, its base feebly convex, nearly twice as long as the straight sloping declivity. Petiole from above elongate-elliptical, broadest in the middle, about one and two-thirds times as long as broad; in profile without a peduncle, nearly as high as long, evenly rounded above and slightly higher just behind the middle, the sides flattened but not marginate above, the anteroventral tooth well- developed, directed downward. Post-petiole less than twice as broad as the petiole, convex and rounded dorsally, ventrally and laterally, slightly broader than long and somewhat narrowed anteriorly. Gaster of the usual shape. Fore femora dilated and convex, somewhat more than twice as long as their median diameter. Somewhat shining; head and thorax more subopaque. Mandibles opaque, very finely and indistinctly punctulate; head and thorax densely punctate, the punctures on the former distinctly coarser; gaster very finely and superficially punctulate. Pilosity and pubescence white, the former short, uneven and sparse on the body, absent on the appendages; the pubescence very fine, short and uniform over the whole surface of the body and appendages, rendering them pruinose. Dark brown; anterior portion of head, gula, sides of pronotum and posterior borders of gastric segments paler, more yellowish brown; mandibles, clypeus, anterior borders of cheeks, antennae, tarsi and tips and bases of femora and tibiae yellow. Female. Length 3-3.2 mm. Very similar to the worker but with the head longer, fully twice as long as broad, with larger eyes and ocelli. Thorax through the wing- insertions slightly narrower than the head through the eyes. Meso- notum subhexagonal, slightly broader than long, very feebly convex in profile. Pronotum more sharply submarginate on the sides than in the worker; epinotum decidedly shorter and more rounded in profile. Petiole longer and more distinctly pedunculate. Sculpture, pilosity and color as in the worker, except that the punctation of the head is finer and the surface, therefore, more shining. Wings hyaline and colorless, with pale yellow veins and pterostigma. Described from numerous workers and two females. This ant was not infrequently found nesting in the cauline swellings of Cordia gerascanthus at Ancon, C. Z., Panama. On one occasion I took it also in a hollow twig of Triplaris americana near Miraflores, C. Z. It is rather closely related to Ps. dolichopsis Forel, elongata Mayr and subtillissima Emery, but cannot be referred to any of these species. wheeler: neotropical ant-plants and their ants 159 Pseudomyrma belti Emery Emery, Bull. Soc. Ent. Ital. 22, 1890, p. 26, 9 9 d\ PL 6, Fig. 1; Biol. Centralbl. 11, 1891, p. 165-168; Anal. Mus. Nac. Costa Rica, 1892, p. 66; Wheeler, Trans. 2nd Ent. Congr. Oxford, 1912, p. 115; Wasmann, Tijdschr. v. Ent. 58, 1915, p. 304; Safford, Smiths. Rep. (1921), 1923, p. 393. The worker measures 5-6 mm. and is black, with the mandibles, border of mouth, antennae, articulations of legs and tarsi reddish. The body is opaque and densely punctate, the abdomen more finely than the head and thorax, the epinotum and summit of petiole also with superimposed foveolae. The pilosity is pale and sparse, the pubescence grayish, appressed and sericeous. The head is ovate, scarcely longer than broad, the eyes occupying less than half its sides, the ocelli small, the anterior border of the clypeus with a narrow, median, truncated lobe, which is not dentate at the corners. Frontal groove distinct, second funicular joint as broad as long, remaining joints, except last, broader than long. The thorax resembles that of Ps. spinicola Emery, but the mesonotum is more convex and pro- jecting and the epinotum is shorter and with a more obtuse angle between the base and declivity. The petiolar node and its peduncle are much shorter, the latter not longer than broad, the former with a small, acute ventral tooth. The postpetiole is broader than long, nearly twice as broad as the petiole, subtriangular, narrowed in front and convex behind. The female measures 8-10 mm. and resembles the worker in sculp- ture, color and pilosity, but has the head one and one half times as long as broad, with rather straight, subparallel sides and straight posterior border. Mesonotum shining, with a blackish or dark brown streak on each side. The wings are infuscated, with dark brown veins and pterostigma. The male was not described, but its head was figured by Emery. It has larger though less convex eyes than spinicola. The species was first taken by A. Alfaro at Alajuela, Jimenez and Siberia, Costa Rica in the thorns of an Acacia which Wasmann believes to have been Acacia spadicigera, but which was probably costaricensis. I possess a cotype worker and numerous workers taken by Dr. P. P. Calvert from Acacia thorns at Santa Cruz, Guanacaste, Costa Rica and numerous workers and a female taken by Dr. J. Bequaert in thorns of Acacia yucatanensis Sehenck at Puerto Castilla, Honduras. 160 bulletin: museum of comparative zoology Subsp. fellosa subsp. nov. Worker. Length 5-5.5 mm. Differing from the typical form of the species in having the sides of the pronotum more distinctly submarginate, the petiole and especially its peduncle longer, the latter stouter and with more prominent spiracles, the node higher, more convex and more sharply truncated behind, the postpetiole broader in proportion to its length and more convex. The sculpture, especially of the thorax, is coarser, the foveolae on the epinotum and petiolar node sharp and discrete. The pubescence and pilosity is longer and more conspicuous. The color is the same, except that the thorax and petiolar peduncle are red, with the dorsal surfaces of the pro-, meso- and epinotum, except their borders, black. There is usually some infuscation of the sides of the thorax, especially of the mesopleura. The mandibles, clypeus and cheeks are brownish yellow, the antennae and legs brownish red, with the femora and tibiae, except their tips and bases, dark brown or blackish. Described from numerous specimens taken by Prof. C. F. Baker at Granada, Nicaragua, in thorns of Acacia costaricensis. I have also a number of specimens taken by Mr. William Fluck in another unre- corded Nicaraguan locality and also in Acacia thorns. Subsp. fulvescens Emery Emery, Bull. Soc. Ent. Ital. 22, 1890, p. 64, 9 9 ; Biol. Centralbl. 11, 1891, p. 167; Anal. Mus. Nac. Costa Rica, 1892, p. 66, nota; Wheeler, Trans. 2nd. Intern. Congr. Ent. Oxford, 1912, p. 117; Forel, Mem. Soc. Ent. Belg. 20, 1912, p. 22 9; Safford, Smithson. Rep (1921), 1923, p. 390, figs. 5 & 6 & PI. 3. Worker. Length 3.5-5.5 mm. Head longer than in the preceding subspecies, fully one and one- third times as long as broad, the punctation finer so that the surface is more shining, the pilosity and pubescence somewhat sparser. Thoracic dorsum straight in profile, mesonotum rather flat; petiole and postpetiole much like those of the typical belli, but the postpetiole is somewhat narrower; the petiolar node varies, being as broad as long in some specimens and somewhat longer than broad in others. Yellowish or ferruginous red, the postpetiole, gaster and legs, except their articulations, usually darker. Female. Length 6.5-8 mm. Head fully one and two-thirds times as long as broad, parallel-sided, wheeler: neotropical ant-plants and their ants 161 the eyes more than twice as long as broad, flattened. Mandibles robust, with convex surfaces and external borders. Epinotum long, its declivity rather abrupt, shorter than the base. Sculpture, pilosity and color much as in the worker; fo veolation of epinotum coarser. Mandibles red, clypeus, antennae and anterior third of head yellow; sides of mesonotum and sometimes the mesopleura castaneous; ocellar region infuscated. Wings grayish hyaline or slightly brownish, with brown veins and pterostigma. Male. Length 6.5-8 mm. Head, including the eyes, distinctly longer than broad, narrowed behind, with rather straight posterior border. Eyes about half as long as the sides of the head. Antennal scapes twice as long as broad; first funicular joint longer than broad. Epinotum rather long, sloping, but with distinct base and declivity. Surface of body more shining and more finely punctate than in the worker and female. Dark brown; mandibles, clypeus, scapes, first funicular joint and tarsi whitish yellow; sides of pronotum, sutures of thorax, bases and tips of femora and tibiae and the borders of the gastric segments yellowish brown. Wings like those of the female. The types of this subspecies were found by Beccari in cauline swellings of Cordia gerascanthus L. from Guatemala, but the occurrence of the ant in this plant must be very exceptional, since it is the com- monest and most widely distributed obligate of the various bull-thorn Acacias in Central America and Mexico. I give here a list of the localities from which I possess specimens: Guatemala: Escuintla, Patulul, Zacapa and Quirigua (Wheeler), in thorns of Acacia hindsii Benth., Acacia sp. bursaria Schenck; Trece Aguas, Alta Vera Paz (Schwarz & Barber). British Honduras: Manatee (J. D. Johnston), in thorns of Acacia sp.; Belize (C. F. Baker), in thorns of Acacia sp. Mexico: Tampico (Ed. Palmer, D. L. Crawford, H. Jourdain); Tonola, Chiapas and Los Cocos, Vera Cruz (A. Petrunkewitch), in thorns of Acacia sp. ; Santa Lucrecia, Vera Cruz (F. Knab); Julapa (Rangel), in thorns of Acacia sphaeraccphala; San Sebastian, Chiapas (G. N. Collins), in thorns of Acacia Collinsi Saff. Pichucalco, Chiapas (G. N. Collins), in thorns of A. cornigera L. ; Llano Grande, Chiapas (G. N. Collins), in thorns of A. hindsii. San Luis Potosi, probably in thorns of A. hernandesi Safford. The subspecies fulvescens is also recorded by Dr. Safford from the following localities in Mexico: Tanquian, San Luis Potosi (L. G. Cuevas), in thorns of Acacia sphaerocephala; Tampico (J. M. Cuaron) 162 bulletin: museum of comparative zoology in 'thorns of the same Acacia; San Sebastian, near Tuxtla (G. N. Collins) in thorns of Acacia collinsi. Subsp. saffordi subsp. nov. Worker. As large as fulvescens and with the head of the same pro- portions, but with the coarse opaque sculpture of the typical belli, the petiole, especially its peduncle shorter than in either of these forms, the node slightly broader than long, the postpetiole also broader than long but only one and two-thirds times as broad as the petiolar node. Mesonotum rather convex and prominent. Dark brown ; anterior por- tion of head, borders of orbits, two longitudinal streaks on the gula, pronotum, sides of petiole, tibia? and tarsi paler, reddish brown. Nine workers taken by Mr. G. N. Collins from thorns of Acacia collinsi Saff. at Chicoasen, Chiapas, Mexico, and received from Dr. Safford. Three small workers and an immature and imperfect female taken by Mr. Collins at Yerba Lanta, Chiapas in the same species of Acacia seem to belong to the same subspecies, although the workers are more uniformly dark brown. I also refer to this subspecies a series of workers from the Department of Solola, Guatemala, 3,000 feet. They have the top of the head black, but the thorax and petiole are uniformly deep brownish red. Subsp. venefica subsp. nov. Worker. Length 3.5-4 mm. Decidedly smaller than the subsp. fcllosa. Head of the same propor- tions. Epinotum longer, the base very convex and decidedly longer than the declivity into which it passes through a convex curve, without an angle. Thoracic sutures very deep and broad. Petiole as in fellosa but the node slightly longer than broad; postpetiole a little broader than long, twice as broad as the petiolar node. Sculpture and pilosity as in fcllosa. Very dark brown, nearly black; clypeus and frontal carinae yellow; mandibles, antennae, thoracic sutures, posterior and lateral borders of pronotum, tarsi, articulations of legs and posterior borders of gastric segments pale reddish brown. Female. Length 5 mm. Head short, less than one and one half times as long as broad, broadest behind the eyes, narrower through the cheeks, which are straight and subparellel. Eyes less than twice as long as broad, feebly convex. Sculpture, pilosity and color as in the worker, but the prono- wheeler: neotropical ant-plants and their ants 163 turn, except its dorsal disc, the whole of the scutellum, the sides and posterior portion of the epinotum and the petiole, except the dorsal surface of its node, yellowish brown. Wings grayish hyaline, not in- f uscated ; veins pale, the pterostigma dark brown. Male. Length 4.-4.5 mm. Head as broad as long, rounded but not narrowed behind. Eyes convex, more than half as long as the sides of the head. Scapes nearly two and one half times as long as broad; first funicular joint longer than broad. Epinotum low and sloping, not very convex. Postpetiole a little longer than broad, behind nearly three times as broad as the node of the slender petiole. Sculpture, pilosity and color like those of the worker, but the head and thorax more shining and more finely punctate; the antennae and legs infuscated; the wings as in the female. Described from numerous specimens of all the phases taken by Mr. J. H. Batty in the thorns of Acacia sinaloensis Saff . at Escuinapa, Sinaloa, Mexico. Another series of workers and dealated females taken ay Mr. C. H. Tyler Townsend in thorns of A. Hindsi at Man- zanillo, Colima, Mexico, may be referred to the same subspecies, though the head of the female is distinctly longer and the pale portions of the thorax and petiole are darker. Of this same subspecies, which is characterized by the small size of all the phases, I have a male, female and worker taken by Prof. C. F. Baker at Acapulco, Mexico. Subsp. vesana subsp. nov. Worker. Length 3.5 mm. Characterized by its small size, pale color and the shape of the pedicel. The petiole is very short, there is almost no peduncle and the node is high, triangular when seen from above, as broad as long; the postpetiole is nearly twice as broad as long and twice as broad as the petiolar node ; rather abruptly narrowed anteriorly. Base and declivity of epinotum subequal, straight, the latter sloping. Head a little longer than in the subspecies vcnefica, punctation of head and thorax some- what finer, foveolse of epinotum and petiolar node less distinct. Yel- lowish red; mandibles and anterior portion of head yellow; legs slightly brownish, postpetiole and gaster dark brown. A single specimen taken by Mr. Fred Knab at Cordoba, Mexico, probably on some species of Acacia. This form is obviously transitional to the subsp. fulvescens in color and sculpture, in the structure of the pedicel, but not in the shape of the head. 164 bulletin: museum of comparative zoology Subsp. bequaerti subsp. nov. Worker. Length 3.5^1.5 mm. Head distinctly shorter than in the other forms of the species, more rounded and elliptical. Sides of pronotum scarcely submarginate. Petiole with well-developed peduncle, the node from above triangular, as long as broad, postpetiole nearly as long as broad. Surface some- what shining and lustrous; the foveolae on the epinotum and petiolar node more indistinct than in the other subspecies. Dark brown, sutures of thorax, petiole and postpetiole, the tarsi, antenna?, greater portion of tibiae, mandibles and anterior half of head reddish; posterior half of head feebly infuscated. Numerous workers taken by Dr. Joseph Bequaert in thorns of Acacia yucatanensis Schenck at Puerto Castilla, Honduras. Subsp. wasmanni Wheeler Pseudomyrma canescens Wasmann {nom. -praeocc.) Tijdschr. Ent. 58, 1915, p. 297 et seq., § 9 c?; Pseudomyrma wasmanni Wheeler, Ecology 2, 1921, p. 92, nota. I have not been able to recognize this form among my material. Wasmann described and figured it from specimens collected by W. Brakhoven in thorns of Acacia sphaerocephala at Tampico, Mexico, and regarded it as an independent species. He did not compare it with the subsp. fulvescens, but with the typical belti and hence made much of the length of the head. The workers observed by Wasmann had the sides of the head sub-parallel, which is not true of any of the forms of belli known to me. The other characters mentioned in his description may nearly all be observed in fulvescens, which is rather variable. The measurements given are: Worker: 5.5-6.5 mm; Female: 7-8 mm.; Male: 7-8 mm. There is nothing in Wasmann's figures to show that his specimens will not admit of the interpretation I have given. Pseudomyrma caroli Forel var. sapii Forel Forel, Zool. Jahrb. Abt. Syst. 20, 1904, p. 688, g 9 . Brazil: Bom Fim, Jurua, Amazonas (E. Ule), in the perforated stems of Sapium (Euphorbiaceae). The typical caroli was described from Costa Rica. I have taken it at Escuintla, Guatemala and have received many specimens of it from Manatee, British Honduras (J. D. Johnston). wheeler: neotropical ant-plants and their ants 165 PSEUDOMYRMA CHODATI Forel Forel, Bull. Soc. Bot. Geneve (2) 11, 1920, p. 1, 8 . Paraguay: (R. Chodat), in the cauline swellings of Cordia longituba Chodat. Pseudomyrma damnosa Wheeler Wheeler, Zoologica 3, 1921, p. 139, 9 9 cf, Fig. 13. Bailey, Bot. Gazette 75, 1923, p. 34. British Guiana : Kartabo, Kalacoon and Penal Settlement (Wheeler) ; in hollow petioles of Tachigalia paniculata Aublet. Pseudomyrma dendroica Forel Forel, Rev. Suisse Zool. 12, 1904, p. 40, g c? ; C. R. 6e Congr. Intern. Zool. Berne (1904), 1905, p. 452. Brazil: Rio Purus, Amazonas (A. Goeldi), in hollow branches of Triplaris. Var. emarginata Forel Forel, Zool. Jahrb. Abt. Syst. 20, 1904, p. 684, 8 9 ; C. R. 6e Congr. Intern. Zool. Berne (1904), 1905, p. 452. Brazil: Marary Jurua, Amazonas (E. Ule), in hollow twigs of Triplaris schomburgkiana Benth. Pseudomyrma elongata Mayr Wheeler, Bull. Amer. Mus. Nat. Hist. 21, 1905, p. 87, 8 9 d\ Florida: Cards' Point (Wheeler), nesting in Tillandsias. Var. tandem Forel Forel, Ann. Soc. Ent. Belg. 50, 1906. p. 228, 8 . Costa Rica: El Hiquito, San Mateo (P. Biolley), in the trunk and fruit of Bixa orellana. 166 bulletin: museum of comparative zoology PSEUDOMYRMA FIEBRIGI Forel Forel, Verh. Zool. bot. Ges Wien 1908, p. 383, S 9 ; Fiebrig, Biol. Centralbl. 29, 1907, p. 68; Chodat and Carisso, Bull. Soc. Bot. Geneve 12, 1920, p. 189, fig. 324, 325. Paraguay: San Bernardino (K. Fiebrig), in thorns of Acacia cavenia H. & A. PSEUDOMYRMA GEBELLI Forel Panama: Las Sabanas (Wheeler), in Tillandsias growing on man- zanillo trees (Hippomanc mancinclla L.) also in branches of almendra (Terminalia catappa), at Ancon C. Z. PSEUDOMYRMA GRACILIS Fabr. Wheeler, Trans. 2nd Intern. Ent. Congr. Oxford, 1912, p. 118. Guatemala: Quirigua (Wheeler), nesting in thorns of Acacia. Panama: Chivachiva Trail, near Red Tank, C. Z. (Wheeler); Tumba Muerta Road, near Las Sabanas (Wheeler), in thorns of Acacia penono- mensis Saff. Bolivia: Riberalta (W. M. Mann), in cauline swellings of Cordia gcrascanthus var. As a rule this ant nests in dead twigs. This is also true of the follow- ing variety. Var. bicolor Guerin The workers are of the same stature as the typical gracilis, black, with the mandibles, clypeus, cheeks and frontal carinae yellow, the thorax and petiole dull orange, with the mesonotum, a large spot and streak on the base of the epinotum, two elongate spots on the prono- tum and the ventral border of the pleura black. The legs are variable, usually black, with the tips of the femora and tibiae yellow, streaked with black on the extensor surfaces. Some of the specimens lack the black spots on the pronotum and some have merely the peduncle of the petiole and the pronotum somewhat reddish and thus form a transition to the true gracilis. The variety resembles the subsp. mexicana Roger but is more slender, with the same stature as the typical gracilis. Panama: Chivachiva Trail, near Red Tank, C. Z. (Wheeler), in cauline swellings of Cordia gerascanthus (common). Same locality in wheeler: neotropical ant-plants and their ants 167 the hollow stems of Triplaris americana. Tumba Muerta Road, Las Sabanas (Wheeler); in fistulose stems of Clerodendron siphona?ithus (introduced from the Orient.) Subsp. mexicana Roger Emery, Biol. Centralbl. 11, 1891, p. 167; Anal. Mus. Nac. Costa Rica 1892, p. 67; Wheeler, Amer. Natural. 35, 1901, p. 527; Ann. Soc. Ent. Belg. 45, 1901, p. 204. Costa Rica: (A. Alfaro), in thorns of Acacia. Mexico: Cuernavaca (Wheeler), in Tillandsia Benthamiana. In internodes of bamboo. Costa Rica (H. Schmitt). Pseudomyrma kuenckeli Emery Emery, Bull. Soc. Ent. Ital. 22, 1890, p. 62; Anal. Mus. Nac. Costa Rica 1892, p. 67; Wheeler, Ann. Soc. Ent. Belg. 45, 1901, p. 203. This ant was originally described from Alajuela, Costa Rica, and as nesting in wood. In his paper of 1892, Emery mentions that he received from A. Alfaro one specimen taken in an Acacia thorn. The further fact that I took this Pseudomyrma in 1900 at Cuernavaca, Mexico, running in considerable numbers on the trunk and branches and living in the dry twigs of small acacias not of the bull-horn type, but prob- ably A. farnesiana, shows that unlike Ps. belli and spinicola, it is only an occasional tenant of the bull-horn Acacias. Pseudomyrma latinoda Mayr Mayr, Verh. Zool. bot. Ges. Wien 1877, p. 877, 2 . The type of this species was taken by Prof. James Trail in Northern Brazil, probably in some myrmecophyte (Triplaris or Tachigalia). Prof. Forel gave me a specimen from Sarayacu, Brazil, which he re- garded as belonging to the typical form and which agrees well with Mayr's description. Probably Forel's dendroica and my maligna and damnosa may be eventually regarded as subspecies of latinoda, but for the present I treat them as distinct species to avoid introducing more confusion into a sufficiently intricate congeries of closely related forms. Var. coronata var. nov. Worker. Length 5 — 5.5 mm. Larger and more robust than other forms of the species. Black, with the head reddish yellow and with the same peculiar markings on 168 bulletin: museum of comparative zoology the occiput as in var. nigrescens {vide infra), only more distinct. Mandibles red, blackish at the base. Antennae and tarsi reddish yellow, somewhat paler than the head; legs dark brown or blackish, with the knees and posterior borders of the gastric segments reddish. Form of body, sculpture and pilosity very much as in nigrescens and with the funicular joints 2-10 very nearly as short and transverse. Male. Length 6 mm. Head and body of the usual shape; eyes half as long as the sides of the head; antennal scapes a little less than twice as long as broad; funiculi short, first joint a little longer than broad, remaining joints, except the last, not more than twice and mostly less than twice as long as broad. Epinotum rounded and sloping, without distinct base and declivity. Petiole and postpetiole much as in the worker. Very smooth and shining, sparsely punctate; ocellar region sub- opaque, finely and densely punctate; sides of thorax indistinctly rugulose. Pilosity like that of the worker, but somewhat less abundant and less even. Piceous black, including the genital valves; mandibles, clypeus, anterior portion of head, antennae, tarsi, articulations of legs, thoracic sutures, portions of pleura and borders of gastric segments, sordid or brownish yellow. Wings distinctly infuscated, with dark brown veins and pterostigma. Described from numerous workers and four males taken by Mr. H. O. Lang at Kamakusa, British Guiana in the hollow petioles of Tachigalia paniculata Aublet. Var. endophyta Forel Forel, Mem. Soc. Ent. Belg. 20, 1912, p. 22, £ . Taken by A. Ducke on the Rio Ariramba, near the Rio Trombetas, Amazonas, Brazil, in the hollow leaf-petioles of Tachigalia macro- stachya Huber. The worker measures 4.1-5.3 mm. and is therefore larger than the typical latinoda which measures only 4 mm., according to Mayr. Endophyta is entirely yellowish red, with a brownish spot in the ocellar region. Var. nigrescens Forel Forel, Rev. Suisse Zool. 12, 1904 p. 38 § . The worker of this variety was taken by Prof. E. A. Goeldi at Para, Brazil, probably in some myrmecophyte (Tachigalia?). It averages wheeler: neotropical ant-plants and their ants 169 about the same size (4.4-4.8 mm.) as endophyta, but has the thorax, abdomen, femora and anterior surfaces of tibiae brown, with the man- dibles, head, tarsi and posterior surfaces of the tibiae and sometimes also the anterior portion of the pronotum, reddish yellow. There is a brown spot covering the ocelli and connected with a transverse band of the same color on the occiput. This band sends off a longitudinal branch towards or to the posterior orbit of each eye. Subsp. bradleyi subsp. nov. Worker. Length 3.5 — 4 mm. Differing from the subsp. tachigaJia? Forel (vide infra) in having the head much less deeply excised behind, with more nearly straight and parallel sides, eyes somewhat smaller, one-third as long as the sides of the head, the frontal groove much more distinct and becoming very deep and broad in front of the anterior ocellus. Mesoepinotal impres- sion decidedly deeper, the petiolar node much thicker in front, scarcely longer than broad, subcuboidal, trapezoidal from above, its ventral surface flat and unarmed. Postpetiole from above semicircular, twice as broad as long. Fore femora slightly more dilated than in tachigaliae. In sculpture, pilosity and pubescence very similar to tachigalice but the vertex of the head somewhat more shining. Color much darker, dark brown, with the gaster blackish; pro- and mesonotum somewhat paler; mandibles, clypeus, anterior third of head and tarsi dull whitish yellow; antennae, femora and tibiae dark brown, knees and bases of funiculi paler. Described from nine workers taken by Prof. J. C. Bradley at Perene, Peru, in the hollow petiole of a Tachigalia. Subsp. opacior Forel Ps. lattnoda var. opacior Forel, Ann. Soc. Ent. Belg. 48, 1904 p. 170 9 . This form was described as a mere variety from Cuba (Coll. Ballion), but it evidently deserves to rank as a subspecies. The worker measures 4.3 mm. and is uniformly dull yellowish brown, with paler antennae and legs. The head is densely punctate and subopaque, the punctua- tion of the remainder of the body is also denser and coarser than in the other forms of the species. The petiolar node is broader than long. The head is more narrowed anteriorly and the anterior slope of the pronotum is less abrupt, the epinotum less rounded and more angular than in the typical latinoda and the var. nigrescens, the only forms with which Forel compares it. 170 bulletin: museum of comparative zoology Subsp. tachigalle Forel Forel, Zool. Jahrb. Abt. Syst. 20, 1904 p. 686 8 9 d\ Forel described all three phases of this ant from specimens taken by E. Ule at Tarapoto, Amazonas, Peru, in the hollow petioles of Tachigalia formicarum Harms. The worker measures 4.5-5 mm. and has the head longer and nar- rower than in the preceding forms, with the posterior border rather broadly and deeply excised. The petiolar node is lower and has two teeth -on the ventral side. Funicular joints, except the first and last, very short and transverse. Body and legs only feebly shining and rather densely punctate, with dense yellowish pubescence, especially on the gaster. The color is a dirty yellowish brown, the anterior por- tion of the head, mandibles, antennae, tarsi, borders of gastric segments, articulations and the nodes of the pedicel in part yellowish. The female measures 9-9.5 mm. and has a longer head than the worker, the mandibles geniculate at the base and marginate externally, with two apical and no basal teeth. The clypeus has a prominent anterior lobe and median carina. The petiolar node is one and one- half times as long as broad and scarcely broader behind than in front. The surface of the body is much more shining than in the worker, rather coarsely and densely punctate. Brownish black or blackish brown, with the cheeks, clypeus, antennal foveas, antennas, tibiae, tarsi, articulations and borders of the gastric segments yellowish red or yellowish. Wings tinged with blackish brown, with blackish brown veins and pterostigma. The male measures 6.2-6.7 mm. The clypeus has a concave border but no median carina. The funicular joints are short, not twice as long as broad, the scape being of about the same length. Eyes small, shorter than their distance from the posterior corners of the head. Sculpture, pilosity and color as in the female, but the membranes of the wings are yellowish, the legs almost entirely yellow, the funiculus, except its first joint, brown. Pseudomyrma maligna Wheeler Wheeler, Zoologica 3, 1921 p. 143 2 9 o 71 ; Bailey, Bot. Gazette 75, 1923 p. 34. British Guiana. Kartabo (W r heeler), in hollow petioles of Tachigalia paniculata Aubl. Var. cholerica Wheeler Wheeler, Zoologica 3, 1921 p. 146 g ; Bailey, Bot. Gazette 75. 1923 p. 34. British Guiana. Kartabo (Wheeler), in hollow petioles of Tachigalia paniculata Aubl. wheeler: neotropical ant-plants and their ants 171 Var. crucians Wheeler Wheeler, Zoologica 3, 1921 p. 147 8 ; Bailey, Bot. Gazette 75, 1923 p. 34. British Guiana. Kartabo (Wheeler) in hollow petioles of Tachigalia paniculata Aubl. Pseudomyrma nigrocincta Emery Emery, Bull. Soc. Ent. Ital. 22, 1890 p. 64 8 9 , PL 6 Fig. 3; Biol. CentralbL 11, 1891, p. 166; Anal. Mus. Nac. Costa Rica 1892, p. 66; Wheeler, Trans. 2nd Intern. Ent. Congr. Oxford 1912, p. 118; Wasmann, Tijdschr. Ent. 58. 1915 p. 304. Costa Rica. Alajuela and Jimenez (A. Alfaro), in thorns of Acacia (spadicigera, according to Wasmann); Guanacaste and Turrucares (P. P. Calvert), in thorns of Acacia sp. Pseudomyrma nigropilosa Emery Emery. Bull. Soc. Ent. Ital. 22, 1890 p. 62 8 PL 5 fig. 24; Biol. Centralbl. 11, 1891 p. 168; Anal. Mus. Nac. Costa Rica 1892 p. 67; Wheeler, Trans. 2nd Intern. Ent. Congr. Oxford 1912 p. 116. Costa Rica (A. Alfaro); in thorns of Acacia; Guanacaste, Santa Cruz (P. P. Calvert), in thorns of Acacia. This ant more frequently nests in dead twigs. Pseudomyrma picta Stitz Stitz, Deutsch. Ent. Zeitschr. 1913 p. 209 8 Fig. 2. This species was described from worker specimens taken by E. Ule at Alto Acre, Brazil, in hollow petioles of Tachigalia. It measures 5.5 mm. and resembles Ps. sericea Mayr in form but is more robust and the head is much larger, flattened, as broad as long, with convex sides and straight posterior border. It has two elongate diverging impressions on the front for the scapes, which reach a little beyond the middle of the head. The clypeus is strongly carinate and has a narrow median lobe, with straight entire border. The frontal groove is distinct and terminates in a deep longitudinal impression in front of the anterior ocellus. The eyes are large, elongate, two-thirds as long as the sides of the head. The thorax is much like that of sericea but broader, with the pronotum and base of epinotum more flattened and more sharply submarginate on the sides. The petiole and post- petiole are also similar to those of sericea, the postpetiole, according to Stitz being broader than the pronotum, with convex posterior border. 172 bulletin: museum of comparative zoology Slightly shining; surface covered rather uniformly with very short dense pubsecence, which is somewhat longer on the gaster. Hairs sparse, much as in sericea, longest and most conspicuous on the abdo- men. Ferruginous yellow, with the anterior portion of the head paler; mandibles sordid brown, with blackish brown dental border. The body is spotted with black as follows : "Deepest portion of frontal groove with a short, black, longitudinal spot; on each side of the vertex, between the lateral ocellus and posterior inner orbit a narrow longitudinal stripe on each side ; on the lower surface of the head behind the eye a broad lon- gitudinal band reaching to the occipital border, most strongly developed under the eye; a very strong median band along the gula to the edge of the occiput. The pronotum has on the transverse ridge (separating its anterior and posterior faces) a round spot on each side, sometimes also one or two spots on its sides. The edges adjoining the mesonotal sutures are marked by a black band. The black color is more extensive on the epinotum ; its basal surface is black, also the adjacent portion of the declivity. Among the spots on the epinotum the most prominent is an elongate ring-shaped spot, which runs obliquely from the middle of the lateral surface to the insertion of the petiole. The anterior sur- face of the petiolar node has three black longitudinal bands, the two lateral of which skirt its borders but pass over on the lateral surface and are broadest behind, where like the median band, they partially extend over onto the posterior surface. The gastric tergites and ster- nites have broad black borders. The coxae are usually dark. The mid- dle and hind femora and tibiae have in the extensor surface at the distal end a longer or shorter, blackish brown stripe; the tarsal joints of these legs are brown with only their tips yellow." Var. heterogyna Wheeler and Mann, var. nov. Worker. Length 4.5 — 5 mm. Smaller than the type but very similar in sculpture, pilosity, color and the shape of the petiole, but the black spots are more variable, the large one in the base of the epinotum often reduced to a median longitudinal band. The postpetiole is shorter and not as broad as the pronotum and with a somewhat concave posterior border. The petiolar node is stouter and shorter, not longer than broad, its anterior surface rather flat, convex only above where it joins the abrupt posterior sur- face. The second funicular joint is as long as broad, the succeeding joints distinctly broader than long. Female (dealated). Length 9 mm. wheeler: neotropical ant-plants and their ants 173 Head large, distinctly longer than broad and strongly rectangular, except in front of the eyes, where it is narrowed. Eyes more than half as long as the head. Mandibles strongly convex. Antennal scapes not reaching to the middle of the head; funicular joints as long as broad. Thorax stout, with convex mesonotum, the promesonotal suture very deeply impressed. Epinotum short, subcuboidal, with distinct base and declivity. Petiolar node subcuboidal, nearly square from above, but slightly narrowed in front. Postpetiole shaped as in the typical pida worker, with convex posterior border, its ventral surface very convex anteriorly. Gaster as in the worker, with pointed tip. Black; tip of gaster, mandibles, anterior two-fifths of head, cheeks, antennae, fore tibiae and tarsi and terminal joints of middle and hind tarsi reddish yellow; knees and posterior borders of gastric segments reddish. The light and dark portions of the upper surface of the head are separated by a sharp, straight, transverse line. The pilosity and pubescence are much as in the worker, the punctuation more distinct, the surface somewhat more shining. Described from eight workers and a single female taken by Dr. W. M. Mann at Cavinas, Bolivia, in the hairy cauline swelling of a species of Platymischium. Subsp. casta subsp. nov. Worker. Length 4.5 — 5 mm. Uniformly opaque and ferruginous, with the extreme bases of the gastric segments blackish, a longitudinal blackish spot on the base of the epinotum and in one specimen with two black spots on the prono- tum; the mandibles and anterior portion of the head yellowish, the antennal funiculi brown. Scapes reaching a little beyond the middle of the head, joints 2-4 of the funiculi as long as broad, the succeeding joints shorter. Base and declivity of epinotum subequal, the former flattened and distinctly submarginate on the sides like the pronotum. Petiolar node from above not longer than broad, stouter anteriorly than in the typical pida, in profile much more convex anteriorly than in both the preceding forms, the line of juncture of the antero-dorsal and posterior surfaces straight and transverse, rather sharp, the lateral surfaces flat, marginate above as in the other forms of the species. Postpetiole convex, shaped much as in heterogyna and bearing the same relations in size to the petiolar node. Described from nine specimens taken by Prof. J. C. Bradley at La Sombre, Putumayo, Peru, in the hollow petioles of Tachigalia. 174 bulletin: museum of comparative zoology pseudomyrma satanica sp. iiov. (Plate 47, fig. b) Worker. Length 5.5 — 6 mm. Closely related to spinicola (vide infra) but somewhat larger. Head slightly longer than broad, somewhat depressed or flattened, broadest through the eyes, as broad through the well-developed posterior corners as at the clypeus, occipital border straight. Eyes larger and more convex than in spinicola, ocelli well-developed. Mandibles rather flat, with 6 subequal teeth, the external borders rather straight. Clypeus very short, convex in the middle, laterally depressed, the an- terior border with a very short lobe which is irregularly excised in the middle and has on each side a triangular, flattened and not very acute tooth. Frontal carina? continued backward as longitudinal swell- ings, much as in spinicola but including a distinct frontal groove which terminates in a short, deep, longitudinal impression in front of the anterior ocellus. Antennae stout, scapes reaching nearly to a line join- ing the posterior orbits; second funicular joint as long as broad, remain- ing joints, except the last, distinctly broader than long. Thorax and pedicel much as in spinicola, but the mesonotum more convex and pro- jecting and the epinotum higher, with subequal base and declivity, the posterior corners of the petiolar node more acute, subdentate, the postpetiole less narrowed and more convex in front, the tooth on the ventral side of the peduncle lacking. Subopaque; abdomen more shining than the head and thorax; punc- tuation coarser than in spinicola and its subspecies. Mandibles rather opaque, more coarsely striato-punctate. Pilosity yellowish, less abundant, pubescence grayish, conspicuously longer and more abundant than in spinicola, well-developed, even on the thorax. Black; postpetiole and gaster dark brown, the posterior margins of the segments of the latter somewhat reddish; mandibles, clypeus and insertions of scapes brownish yellow; antennae, lateral borders of pro- notum and legs reddish brown, the median portion of the scapes, fe- mora and tibiae darker and more blackish. Female. Length 8 — 8.5 mm. Very similar to the worker, except in the shape of the head, which is subrectangular, nearly one and three-fourths times as long as broad, with nearly parallel sides and straight posterior border. Eyes large and elongate, more than two-fifths as long as the sides of the head. Clypeal lobe more rectangular and longer than in the worker, frontal wheeler: neotropical ant-plants and their ants 175 groove distinct but not terminating behind in an impression. Mandi- bles robust, rather flattened at the tips, with rounded, convex external borders. Thorax shaped much as in spinicola subsp. scelerosa, but the epinotum is shorter and more rounded. Posterior corners of petiolar node large, prominent, subdentate and somewhat turned outward. Postpetiole longer than broad, nearly parallel-sided behind, rounded and narrowed in front. Sculpture, pilosity, pubescence and color much as in the worker, but the punctuation coarser, especially on the epinotum and petiolar node and the pubescence on the head and gaster longer. Wings deeply in- fuscated as in spinicola subsp. scelerosa, with dark-brown veins and pterostigma. Male. Length 6.5 — 7 mm. Very similar to the male of spinicola subsp. scelerosa, but the head is longer and more produced behind the eyes, the latter more convex, the first funicular joint only as long as broad, the epinotum less convex and more sloping, the petiole more convex above. Wings scarcely paler than in the female. Described from numerous specimens taken near the headwaters of the Rio Agua Salud, C. Z., Panama, and Marajal, near Colon, C. Z. They were inhabiting the large straight thorns of two superb trees about 12 feet high of Acacia multiglandulosa Schenck. The ants are extremely aggressive, fiercer even than belli and spinicola and their stings are more painful. I should have attached this form as a sub- species to spinicola were it not that its behavior is quite different. Instead of advancing to the attack like belli and spinicola, with the gaster turned forward under the thorax, it keeps its body rigid with the gaster extended as in Ps. gracilis Fabr. and turns it forward to sting only after seizing the intruder with its mandibles. Multiglandulosa is one of the most beautiful of the bull-horn acacias. Its foliage is heavy, spreading and bright green, the large leaves each with 8-15 pinnae, the pinnules when young tipped with golden yellow food-bodies. There are numerous extrafloral nectaries on the base of the petiole and one between each pair of pinnse. The handsome thorns, when young, are bright crimson. PSEUDOMYRMA SERICEA Mayr (Plate 48, fig. a) Forel: Zool. Jahrb. Abt. Syst. 20, 1904 p. 691 2 9 ; Ann. Soc. Ent. Belg. 50, 1906 p. 230. 176 bulletin: museum of comparative zoology Brazil: Jurua Miry, Jurua, Amazonas (E. Ule), in the swollen flower axes and twigs of Pterocarpus ulei Harms. Bom Lugar, Rio Purus, Amazonas (J. Huber and A. Goeldi), in the hollow twigs of Bombax mungaba. Var. acaciarum var. nov. Worker. Length 3 — 3.5 mm. Closely related to the var. ita Forel of Costa Rica, but smaller. The petiole and postpetiole are similar but the dorsal surface of the former is even less convex and distinctly marginate in the sides and behind, the posterior surface sharply truncated and flat. Seen from behind the sharp angle at which these surfaces meet is straight and transverse. Postpetiole nearly twice as broad as the petiolar node. Thorax and head much like those of the var. ita. Pubescence white, sericeous, much more abundant than in ita, so that the surface is pruinose. Black; mandibles, clypeus, antennse, sides of pronotum, neck, fore tibia? and tarsi and tips of fore femora brownish yellow ; a fuscous spot on each mandible, the extensor surface of the funiculus and a long black spot on the tip of the scape black. Female. Length about 4.3 mm. Head fully one and one-half times as long as broad. In other respects much like the worker. Wings whitish hyaline, with colorless veins and pale brown pterostigma. Male. Length 4 — 4.5 mm. Head longer than broad, elliptical. Eyes nearly two-thirds as long as its sides. Mandibles long, well-developed, deflected at the tip, their straight apical borders minutely denticulate. Scapes one and one-half times as long as broad, first funicular joint as long as broad. Thorax narrow, the dorsal surface in profile rather straight, sloping backwards, epinotum with subequal base and declivity. Petiole and postpetiole similar to those of the worker, the nodes lower and the surfaces more rounded. Black; mandibles, clypeus, antennae, coxae, legs and pronotum ivory yellow, the mandibles with a large black spot in the middle; clypeus infuscated in the middle, antennae at the tips; the pronotum with a dark brown transverse streak on the dorsal surface, femora feebly infuscated in the middle. Wings colored as in female. Several colonies of this ant were found nesting in the thorns of Acacia penonomensis Saff. along the Tumba Muerte Road, near Las Sabanas, in the Panamanian Republic. wheeler: neotropical ant-plants and their ants 177 Var. cordle Forel (Plate 48, fig. b) Forel, Zool. Jahrb. Abt. Syst. 20, 1904 p. 690 § 9 ; Bull. Soc. Bot. Geneve (2) 11, 1920 p. 2 8 *>*.• PLATE 22 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 22 Acacia Collinsii Safford (=yucatanensis Schenck). Vicinity of Merida, Yuca- tan, Mexico. Photograph by W. E. Collins. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 22 PLATE 23 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 23 Acacia Cookii Safford. Alta Vera Paz, Guatemala. Photograph by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate23 PLATE 24 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 24 Acacia Cookii Safford. Alta Vera Paz, Guatemala. Photograph by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 24 PLATE 25 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 25 Acacia cornigera L. (=Hernandezi Safford). Rascon, San Luis Potosi, Mexico. Photograph by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ante. Plate25 aT~ PLATE 26 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 26 Acacia cornigera L. (=Hernandezi Safford). San Martin, Chalchicuana, Tamazunchale, Huasteca Region, San Luis Potosi, Mexico. Photograph by W. E. Safford. BULL. MUS. COMP. 2COL. Wheeler. Ant Plants and their Ants. Plate26 PLATE 27 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 27 Acacia cornigera L. (=Hernandezi Safford). Huasteca Region, San Luis Potosi, Mexico. Photograph by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 27 PLATE 28 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 28 Acacia cornigera L. Green house plant grown from seed, Washington, D. C. Photograph by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 28 "J PLATE 29 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 29 a. Acacia cornigera L. Green house plant grown from seed, Washington, D. C. Photograph by W. E. Safford. b. Acacia cornigera L. Photograph of type of Acacia spadicigera Schl. and Cham., in Halle Herbarium. BULL. MUS. COMP. ZOOL Wheeler. Ant Plants and their Ants. Plate 29 PLATE 30 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 30 a. Acacia costaricensis Schenck ( = penonomensis Safford). Alajuela Costa Rica. Photograph by W. E. Safford. b. Acacia costaricensis Schenck ( = penonomensis Safford). Penonome, Panama. Photograph by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate30 \ \ /mm ' h t ' '.£, /. -•AS PLATE 31 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 31 Acacia dolichocephala Safford. North of city of Vera Cruz, Mexico. Photo- graph by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate31 PLATE 32 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 32 Acacia donnelliana Safford. Type, San Pedro^Sula, Dept. Sa. Barbara, Honduras. Photograph by W. E. Safford. BULL. MUS. CO MP. ZOOL. Wheeler. Ant Plants and their Ants. Plate32 ■jP» - t PLATE 33 Wheeler — Neotropical Ant-Planta and their Ants. PLATE 33 a. Acacia donnelliana Safford. Type, San Pedro Sula, Dept. Sa. Barbara, Honduras. Photograph by W. E. Safford. b. Acacia globulifera Safford ( = chiapensis Safford). Type, northern Yucatan, Mexico. Photograph by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 33 til > PLATE 34 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 34 Acacia, Hindsii Bentham. Acapulco, Guerrero, Mexico. Photograph by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 34 PLATE 35 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 35 Acacia Hindsii Bentham. Manzanillo, Colima, Mexico. Photograph by W. E. Safford. BULL MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate35 PLATE 36 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 36 Acacia Hindsii Bentham ( = tepicana Safford). Type of tepicana, from Tepic, Mexico. Photograph by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 36 PLATE 37 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 37 a. Acacia melanoceras Beurling ( = multiglandulosa Schenck). Marajal near Colon, Panama. Photograph by D. Fairchild. b. Acacia melanoceras Beurling ( = multiglandulosa Schenck). Marajal near Colon, Panama. Photograph by J. Zetek. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 37 I PLATE 38 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 38 a. Acacia melanoceras Beurling { — multiglandulosa Schenck). Marajal near Colon, Panama. Photograph by J. Zetek. b. Acacia melanoceras Beurling ( = multiglandulosa Schenck). Marajal near Colon, Panama. Photograph by D. Fairchild. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 38 PLATE 39 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 39 Acacia Nelsonii Safford. Acapuleo, Guerrero, Mexico. Photograph by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 39 PLATE 40 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 40 Acacia nicoyensis Schenck. Nicoya, Costa Rica. Photograph by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 40 PLATE 41 Wheeler — Neotropical Ant-Planta and their Ants. PLATE 41 Acacia sphaerocephala Schlecht. and Cham. (=veracruzensis Schenck). Photograph of type of sphaerocephala in Berlin Herbarium. Actopan, State Vera Cruz, Mexico. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 41 PLATE 42 Wheeler — Neotropical Ant-Plants and their Anta. PLATE 42 Acacia sphaerocephala Schlecht. and Cham. ( = veracruzensis Schenck). From a plant grown in Darmstadt from seeds collected in sand dimes south of the city of Vera Cruz, Mexico. Photograph by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 42 PLATE 43 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 43 Acacia sphaerocephala Schlecht. and Cham. ( = veracruzensis Schenck). Dunes of Vera Cruz, Mexico. Photograph by A. Dampf. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate43 PLATE 44 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 44 Acacia Standleyi Safford. Mexico. Photograph of type by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 44 PLATE 45 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 45 Acacia turgida Safford (apparently not published). Herba Santa, Chiapas, Mexico. Photograph by W. E. Safford. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate45 ~* \J- PLATE 46 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 46 a. Dipterous galls on leaflets of Acacia "cornigera". Escuintla, Patulul, Guatemala. b. Dipterous galls on twigs of Acacia costaricensis, near Panama City. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate46 PLATE 47 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 47 a. Pseudomyrma alliodorse. Wheeler. Head of female and worker; thorax and petiolar nodes of worker. b. Pseudomyrma satanica Wheeler. Head of worker and female; thorax and petiolar nodes of worker. BULL. MUS. COMP. ZOOL Wheeler. Ant Plants and their Ants. Plate 47 PLATE 48 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 48 a. Pseudomyrma sericea Mayr. Thorax and petiolar nodes of worker. b. Pseudomyrma sericea var. cordiae Forel. Head, thorax and petiolar nodes of worker. BULL. MUS. COMP. ZOOL Wheeler. Ant Plants and their Ants. Plate48 PLATE 49 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 49 a. Pseudomyrma sericea var. fortis Forel. Thorax and petiolar nodes of worker. b. Pseudomyrma tenuis Mayr. Head, thorax and petiolar nodes of worker. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ant3. Plate49 PLATE 50 Wheelee — Neotropical Ant-Plants and their Ants. PLATE 50 Pseudomyrma triplaridis subsp. baileyi Wheeler. Head of worker and female; thorax and petiolar nodes of worker. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 50 PLATE 51 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 61 a. Pseudomyrma triplarina var. loewensohni Forel. Head of female and worker; thorax and petiolar nodes of worker. b. Leptothorax (Goniothorax) echinatinodis subsp. dalmasi Forel. Head, thorax and petiolar nodes of worker. BULL. MUS. COMP. ZOOL Wheeler. Ant Plants and their Ants. Plate 51 PLATE 52 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 52 Cryptocerus (Cyathocephalus) pattens Klug var. porrasi Wheeler, a, soldier; b, head of same, dorsal view; c, worker. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 52 PLATE 53 Wheeleb — Neotropical Ant-Plants and their Ants. PLATE 53 Cryptocerus (Cyathocephalus) setulifer Emery, a, soldier; b, head of same, dorsal view; c, worker. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 53 PLATE 54 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 54 Cryptocerus (Cyathocephalus) varians F. Smith. Soldier and head of same; worker. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants ano their Ants. Plate 54 %t^^:i- T' ^* c . fgfi&fe"©'f> - © *» e^ ® !?Pc E&V* '■ * ^ ' * £ ' e ' ® » * ' && ° &V?L-- ; © e © « « *.* &s «C ;s.ef •-.^' - »-.■ .. ■.•.vf.--V.*<, PLATE 55 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 55 a. Azteca longieeps Emery. Head of female, workers and male; thorax and petiolar node of worker. b. Azteca pittieri Emery. Head of female and worker; thorax and petiolar node of worker. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 55 PLATE 56 Wheeler — Neotropical Ant-Plants and their Ants. PLATE 56 a. Azteca prorsa Wheeler. Head, thorax and petiolar node of worker. b. Azteca theresiae var. menceps Forel. Head of female and workers; thorax and petiolar node of worker. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate56 PLATE 57 Wheeler — Xeotropical Ant-Plants and their Ants. I PLATE 57 a. Azteca xanthochroa (Roger). Head of female and workers; thorax and petiolar node of worker. b. Camponotus (Paracolobopsis) patimae Wheeler. Head, thorax and petiolar node of worker. BULL. MUS. COMP. ZOOL. Wheeler. Ant Plants and their Ants. Plate 57 Bulletin of the Museum of Comparative Zoology AT HARVARD COLLEGE Vol. XC, No. 2 .*r zoology V V OCT 28 1942 ***** THE LEPIDOPTERA OF BARRO COLORADO ISLAND, PANAMA. No. 2 By William T. M. Forbes Cornell University, Ithaca, New York With Eight Plates CAMBRIDGE, MASS., U.S.A. PRINTED FOR THE MUSEUM October, 1942 PUBLICATIONS OF THE MUSEUM OF COMPARATIVE ZOOLOGY AT HARVARD COLLEGE The Bulletin and Memoirs are devoted to the publication of investigations by the Staff of the Museum or of reports by spec- ialists upon the Museum collections or explorations. Of the Bulletin, Vols. I to LXXXIX, Vol. XC, No. 1 and Vol. XCI, No. 1 and No. 2 have appeared and of the Memoirs, Vol. I to LVI. These publications are issued in numbers at irregular intervals. Each number of the Bulletin and of the Memoirs is sold separately. A price list of the publications of the Museum will be sent upon application to the Director of the Museum of Comparative Zoology, Cambridge, Massachusetts. Bulletin of the Museum of Comparative Zoology AT HARVARD COLLEGE Vol. XC, No. 2 THE LEPIDOPTERA OF BARRO COLORADO ISLAND, PANAMA. No. 2 By William T. M. Forbes Cornell University, Ithaca, New York With Eight Plates CAMBRIDGE, MASS., U.S.A. PRINTED FOR THE MUSEUM October, 1942 . ■ ,1 . OCT 28 1M2 vJL < B k A *V No. 2. — The Lepidoptera of Barro Colorado Island, Panama. No. 2 l By William T. M. Forbes TABLE OF CONTENTS PAGE Introductory Remarks 268 Additional Records for Families in First Report .... 269 Remaining Families . . 286 Family Sematuridae 287 Sematura 289 Family Thyatiridae 290 Family Lasiocampidae 290 Tolype . .292 Artace 293 Euglyphis 294 Family Eupterotidae 303 Epia 305 Colla 306 Quentalia 306 Anticla 308 Tamphana 309 Zanola 309 Apatelodes 310 Olceclostera 312 Family Uraniidae 314 Urania 315 Family Epiplemidae 315 Syngria 317 Syngriodes 318 Schidax 319 Psamathia 319 Nedusia 320 Erosia 320 Gathynia 322 Antiplecta 324 Thysanocraspeda 325 1 Published with the aid of a special gift from Mr. George R. Agassiz. 266 bulletin: museum of comparative zoology Skaphion Bicavernosa Tricolpia Epiplema Family Mimallonidae Mimallo Cicinnus Psychocampa Trogoptera . Bedosia Lacosoma Zaphanta Menevia Alheita . Aleyda Family Thyrididae Dysodia Ochrothyris . Herdonia Hypolamprus Rhodoneura Zeuzerodes . Risama . Draconia Family Castniidae Castnia Family Cossidae Xyleutes Cossula Miacora Givira . Langsdorfia Inguromorpha Family Psychidae Family Zygaenidae Harrisina FORBES: LEPIDOPTERA OF BARRO COLORADO 267 PAGE Family Eucleidae 370 Sibine 373 Euclea 375 Talima 379 Tanadema 380 Semyra 380 Euphobetron 383 Euprosterna 383 Narosopsis 384 Natada 385 Perola 387 Palaeophobetron . . 388 Epiperola 390 Dichromapteryx 391 Prolimacodes 391 Family Dalceridae 392 Acraga 393 Acragopsis 395 Family Megalopygidae 395 Microrape 397 Mesoscia . 397 Norape .398 Trosia 399 Megalopyge 402 Podalia 403 Family Hepialidae 404 Dalaca 405 268 bulletin: museum of comparative zoology INTRODUCTORY REMARKS This article continues a study of the so-called Bombycine Lepi- doptera, published as Bulletin Vol. 85, No. 4 of this Museum. It was issued in August, 1939, and was illustrated with eight plates, containing a total of 66 figures, numbered consecutively. The first article reported on various families, related to the Noctuidae, namely, those which possess a thoracic tympanum. These families were the Euchromiidae, Nolidae, Arctiidae, Pericopidae, Agaristidae, Lyman- triidae, Notodontidae, and Dioptidae. This second article contains an account of fifteen families, mostly small in size, with varied and, on the whole, generalized structure. They include all the remaining so-called Bombycine Lepidoptera except the Saturnid complex, which Dr. Marston Bates had originally intended to study. Under the present circumstances further reports of this series will be indefinitely postponed. The treatment in this report follows that of the first one exactly. The diagrams of seasonal records or flight periods are identical in form. Keys to genera and species have been included, including a few extralimital forms. Positive and probable synonyms have also been freely included. For convenience the figures continue the numbering in the first article; figs. 67-127 are arranged in plates 9-16. Much the larger part of the material used is identical with that listed in detail in the first report, to which the reader is referred. Details of the manner of collection will consequently be given only in cases of special interest. The chief defect of this earlier material was the great gap in the summer months. This gap has been very nicely filled by a collection made by Mr. N. S. Scrimshaw from the middle of June to the first week of August, 1940. Our only serious gap is now September, though no really intensive collecting has been done in April and May. The most noticeable change in the picture, resulting from the Scrim- shaw collection, is the indication that a good many species fly almost continuously, though there are quite a number with well marked flight periods. The Scrimshaw material is not all mounted as yet, but what is available seems to be a fair sample, covering the whole period, and I doubt if the complete lot will alter the picture materially, except possibly in the obscure and fragile Nolidae and Lithosiinae. The first section of this report consequently gives the summer flight data for those families treated in the first article, based mainly on the Scrimshaw collection. Additional genera and species new to Barro Colorado Island, are inserted in the proper systematic sequence, and discussed and treated in the method followed in both papers. FORBES: LEPIDOPTERA OF BARRO COLORADO 269 Additional Records for Families in first Report Family EUCHROMIIDAE Diagram I ADDITIONAL RECORDS OF BARRO COLORADO ISLAND BOMBYCES (Scrimshaw Records for June-August) Month June July Aug. Total NAME Week 12 3 4 12 3 4 12 3 4 P. aliena H. stictosoma oo • OS • 10 G. salvini • • •••• • 33 G. colona • • ••• 12 P. paucipuncta o • • 5 M. pyrrha • oo • 7 M. ethela o o • 4 C. echemus • •oo 8 C. tabascensis C. saron 0* •oo o 8 C. metallescens o oo o 9 C. hercynacula S. clusia o o o 3 S. nox • o* o 8 S. phoenicosticta • o • 6 S. anselma S. afflicta o • o 4 P. thoracica •• o •• • 45 D. correbioides M. auripes o oo o 4 M. cyllarus C. tiburtus • • •• • 35 M. achrysa o o 2 H. restricta o • 3 E. obscurata D. rubricincta E. obscurum o o 2 C. afnnis C. e. germana • • 4 C. e. costinotata C. e. elegans •o o 5 C. e. striata o 1 270 bulletin: museum of comparative zoology ADDITIONAL RECORDS OF BARRO COLORADO ISLAND BOMBYCES — Continued (Scrimshaw Records for June-August) Month June July Aug. Total NAI Week 12 3 4 12 3 4 12 3 4 A. marg. & biop. A. sericea An. intervenata oo • • 8 T. grisescens • o o 4 w < T. alba £ 0. sixola • o o 4 1— 1 m O n I. opulentana G.? phelina G. paidicus ^ L. sordida 0% o«o« • 15 D. falsimonia o 1 Di. coroides o 1 R. sanea O o 2 I. hippia o o 2 E. aberrans N. cotes • ••• • 24 A. critheis • o • • 15 A. obscurata A. sicilia o o o 3 < M. incerta • • ©<:;>• o 15 M. asana • • • • 12 H M. laodamia o 1 B. haemorrhoides < T. imperialis o# • 5 H. maroniensis H. sobrina o 1 H. grandis H. catenuiata o 1 A. minuta A. semivitrea o • • 11 B. pervenosa • o 4 V. rosenbergi •o •••• • 33 E. icasia • o 3 FORBES: LEPIDOPTERA OF BARRO COLORADO 271 ADDITIONAL RECORDS OF BARRO COLORADO ISLAND BOMBYCES— Continued (Scrimshaw Records for June-August) Month June July Aug. Total NAME Week 12 3 4 12 3 4 ' 12 3 4 vinasia purpurascens o 1 S s. corydona • c. marmorea • • o «o 9 c. arema c. rufescens o 1 p. xylinoides o 1 N. superciliosa • • o o 11 N. lophocera • • • • 13 L. concordens L. mixta L. maltha •o • 7 T. pachydexius • o T. albosigma oo o • 5 A. multilinea C. striolata D. guarana o o 2 Di. argentilinea A. divisula oo • o 6 A. rufinsulae o 1 K. muscosula gelduba o • o 4 lama • o 4 R E D. perplexa £ D. tharis o • 3 O R. distinguenda o o 2 R. apella o o 2 | M. multilinea •oo • 7 O g D. morona o • • 8 H. indistans • •o o o 8 H. plana oo •oot o 15 H. commentica o 1 H. plusiata o o 2 H. Colombia • • €'•• • 15 H. vecina H. flava o 1 H. dentata • • o 8 H. meona o 1 H. nigrescens • 2 H. sparsipennis oo o« 5 H. conspirata H. vinicosta oo • 5 H. subochraceum o o 2 Ha. curvilinea • o 4 Ha. repandens o ••o o 7 Ha. simplex o 1 A. lichyi o« 4 C. rarata o o 2 Q Sc. leucophleps •• • •• • 25 272 bulletin: museum of comparative zoology EUCHROMIIDAE Homoeocera stictosoma. A definite summer flight. See diagram. Gymnelia beata. Mar. 1, '33 (A.M.N.H.). Gy. sahini. See diagram for further dates i Gymnelia jansonis Butler Gymnelia jansonis Btl., Cist. Ent., 1, 116, 1872. Figured: Butler, Lep. Exot., 61: 17; Seitz, 2: b2. Abdomen with orange on edges of segments (as in beata) and first segment pale yellow above (as in perniciosa), but no orange on fore wing above. June 26 (Scr.). Costa Rica to Colombia. Gymnelia colona. A definite flight in midsummer (see diagram). The species is presumably not limited seasonally. Phoenicoprocta paucipuncta. See diagram. Phoenicoprocta insperata Walker Poecilosoma insperata Wlk., List Lep. Ins. Br. Mus., 7, 1606, 1856; Leucotmemis i. Hmps., Cat. Lep. Phal., 1, 224; 8: 25, 1898; Cosmosoma i. Zerny, Lep. Cat., 7, 66, 1912. Phoenicoprocta rubiventer Hmps., Cat. Lep. Phal., 1, 198, fig. 94, 1898. Also figured: Seitz, 12: cl (as rubriventris) . July 2 (Scr.). Pheia albisigna. July 23 (Scr.) Loxophlebia fiavipicta. July 3, 9 (Scr.) L. leucothema. June 24 (Scr.) Mesothen pyrrha. See diagram. Mesothen ethela. See diagram. Chrostosoma echemus. See diagram. The summer specimens taken are too few to change the picture, and are probably stragglers. Cosmosoma saron. See diagram. C. metallescens. See diagram. Did not dominate over the preceding species as it did in the winter collection. C. batesi. Mar. 23, '33 (A.M.N.H.) June 23 (Scr.), a specimen with only a black bar on the vertex. C. xanthostictum. A poor specimen, July 30, may be this species. C. remotum. Four specimens cover the period (Scr.) C. teuthras. Eight specimens, June 21-Aug. 6, seem to indicate summer as the proper flight period. FORBES: LEPIDOPTERA OF BARRO COLORADO 273 C. stibostictum. Nine specimens, from June 22 to Aug. 6, again indicate a principal flight in summer. Saurita clusia. Three stragglers (see diagram). P. albicolUs • o o o • o o o • o •• • • o • o • • • © © o o • • o • © 16 17 34 D. assa o • •• • 35 O — 1 capture in this week. — 2 or more captures in this week. F taken by Fairchild in July or early August. FORBES: LEPIDOPTERA OF BARRO COLORADO 289 References Guenee, Hist. Nat. Lep. Het., 9, 16-23, 1857, with pi. 1 (as Sematuridae). Sharp, Cambridge Nat. Hist. Ins., 2, 419, 1899 (larva of Coronidia). Forbes, Jour. N. Y. Ent. Soc, 25, 47, 1917 (in key only, as Coronidiinae). Hampson, Novit. Zool., 25, 367-376, 1918 (as Sematuridae). Dalla Torre, Lep. Cat., 30 (2), 9-15, 1924 (as Coronidiinae). Biol., 2, 4-8, 525, pis. 41, 98; Seitz, 6, 831-837, pis. 138, 139; p. 830 (larva and pupa after Fassl). Key to Genera 1. Tibiae spinulated; tail of hind wing spatulate and twice as long as wide; male without frenulum hook Sematura Tibiae unarmed; tail of hind wing short or not spatulate (absent in Anurapteryx); male so far as examined with a functional though minute frenulum hook Coronidia Sematura Dalman {Mania Hiibner, not Treitschke 1 ; Manidia Westwood) This genus has only three representative species, the present one from the Amazon northward, the hardly distinct S. diana from south Brazil, and S. aegistus F. from the Greater Antilles. The latter is quite distinct, with scalloped transverse banding; and it even breaks up into minor island races. Sematura lunus Linnaeus tfPhalaena Noctua lunus L., Syst. Nat. (Ed. 10), 508, 1758; Cramer, Pap. Exot., 3, 13, 200: A, 1782. 9 Papilio Eques empedocles Cr., Pap. Exot., 3, 11, 199: A, B, 1782. tfManidia selene Guenee, Sp. Gen. Lep. Het., 9, 18, 1857. c?S. actaeon Fid., Reise Novara, Lep., 121 : 5, 1874 (cf as 9 ). Also figured: Hbn., Samml. Exot. Schm., 1, 202: 3, 4 ( 9 as empedoclaria) ; Seitz, 138: cl d\ 4 9 ; 139: al d\ 5 9 as selene). Early Stages: Kirby, I.e. Male with more buff ground, female with contrasting luteous post- medial stripe, etc., otherwise dull brown on luteous. Female with extremely long third segment of palpus. The spatulate tail has two large ocellate spots. All works keep lunus and empedocles as separate species, but the large number I have seen run all lunus d 1 , empedocles 9 . May 27, June 4, 22 (Fried.) Mexico to Brazil; represented by the slight race diana Gn. in southern Brazil. > In fact Mania Hiibner 1823, is valid over Mania Tr. 1825, but only the latter has had any currency in the last century. 290 bulletin: museum of comparative zoology [THYATIRID^l Mostly stout-bodied, Noctuid-like moths, with Sc and R of hind wing closely parallel beyond the end of the cell, and tympanum point- ing backward at rear of first segment of abdomen. Larva smooth, with head decidedly wider than high, living in a folded leaf. Thyatira mexicana H. Edw. (Seitz, 172: i3) ranges from Arizona to Peru or further, and will certainly be found in the Canal Zone. It is mottled gray-brown, with contrasting pale patches, and the larva is probably dead-leaf brown, with oblique lateral shading. The related European T. batis feeds on Rubus.] LASIOCAMPID.E Very stout and heavy moths. Head small and retracted, palpi moderate to small, but remaining mouth parts absolutely vestigial; ocelli and chaetosema absent; antennae broadly pectinate in male and almost invariably in female also. Vestiture of body deep and fluffy, of wings deep, soft, formed of two kinds of scales, one or both of which are often much modified, frequently reduced to forked hairs; — the wings sometimes translucent as a result. Fore wing with R 4 and 3 long- stalked, rarely united, R5 stalked with Mi and sometimes R 3 from their base, M 2 arising near lower angle of cell and Cu 2 very close to base, often easy to mistake for 1st A, which is absent. Hind wing with humeral angle much widened, without frenulum, and supported by one or more humeral veins, arising from a humeral cell (at least in part) ; M 2 as in fore wing, but Cu 2 from further out on cell. All veins extremely stout, the moth frequently being able to expand its wings without letting them hang down. These so-called humerals are fully supplied by tracheae. Larva stout and normally much flattened, with tufts from lateral lappets on body; the hair dense and fine, mostly secondary, but with the hairy warts often diffuse or obscure; secondary hair present even on mouth-parts; hooks of prolegs biordinal. Cocoon normally heavy, often double and often with the meshes filled with a gummy or pow- dery secretion; pupa finely hairy. A large and world-wide family, but most at home in the old world tropics; America has few genera, but Euglyphis is rich in species. All structures are plastic, and tribes and genera as well as species are difficult to define. FORBES: LEPIDOPTERA OF BARRO COLORADO 291 References Hampson, Fauna of British India, Moths, 1, 402, 1892 (first clear recogni- tion of family). Aurivillius, D.E.Z. Iris, 7, 121-185, 1894 (includes first key and analysis of larvae — Palaearctic only). Dyar, Can. Ent., 30, 2-6, 1898 (first key including neotropical genera). Tutt, British Lep., 2, 434-3, 229, 1900, 1902 (monograph). Forbes, Ann. Ent. Soc. Amer., 3, 110, 1910 (family definition on larval characters). Mosher, Bull. 111. St. Lab. Nat. Hist., 12 (2) 123, 1916 (pupal characters) (Omitted by Lep. Cat.). Forbes, Lep. N. Y., (Cornell Mem. 68) 679, 1924 (definition of family on imago and larva). (Omitted by Lep. Cat.). Aurivillius, Seitz' Macrolep. World, 14, 205, 1927 (principal subdivisions of family — treated as subfamilies). Draudt, Seitz' Macrolep. World, 6, 565-628, pis. 75-86, 1927-1928 (Amer- ican species). Collier, Lep. Cat., 73, 1-484, 1936 (full bibliography) . Biol., 1, 200-208; 2, 428-431, pis. 22, 85. Key to Genera 1. Humeral cell good-sized, rounded-trapezoidal, with the free part of Sc arising from near its apex, which diverges from the discal cell (Lasiocampini (fig. 72); eyes large and hairy, palpi long and beak-like; R 3 short-stalked, running to apex or outer margin Prorifrons Humeral cell small and fusiform, apparently cut out of the basal angle of the discal cell (figs. 71, 74, etc.); Sc and frequently second humeral vein also, arising directly from discal cell (Malacosomatini) 2 2. Hind wing with only one humeral vein (figs. 73, 74), which may have minute anterior branches; M 2 slightly separate from M 3 at origin; fore wing with R 2 and R 3 long-stalked, usually much farther than R 5 is stalked with Mi, R 4 strongly stalked with R5 + Mi; palpi hardly exceeding front 3 Hind wing with two humeral veins (fig. 71), the second arising at or beyond end of humeral cell and sometimes stalked with Sc; costa strongly arched, M 2 and 3 generally short-stalked; fore wing with R 2 and 3 usually forking about opposite the fork of R 5 from Mi; R 4 very short-stalked or free; palpi moderate Euglyphis 292 bulletin: museum of comparative zoology 3. Body with a massive middorsal crest on disc of thorax, basal third or more of abdomen, or both Tolype Whole body clothed with smooth fine decumbent hair and hair- scales Artace Dyar describes Prorifrons castullux from the Canal Zone; it is brown with five pale shaded transverse lines (Seitz., 76: el). Tolype Hiibner (including Titya Walker) This genus falls into three main groups on the nature of the dorsal tufting. In the typical (mostly North American) species the disc of thorax and extreme base of abdomen have large shining spatulate scales, contrasting with the fine hairy vestiture of collar and tegulae; in the phyllius group the spatulate scales do not contrast, and are extended further back on the abdomen, also the vestiture of the collar and tegulae is noticeably flattened or spatulate. The residue, includ- ing the Tityas and many species now standing as Tolype, have all the hair fine, but raised in a broad crest almost the whole length of the abdomen. (Venation fig. 73.) The normal larvae are strongly flattened, with strong sidelappets, and with a contrasting (blue) band across the posterior edge of the thorax (but see T. synoecura, below). They are tree feeders, and the cocoon, which is strong and flat, is formed on the bark of the tree. 1. Dorsal vestiture spatulate, very dense but nearly smooth; buff, the fore wing shaded with blackish toward apex, contrasting with a broad pale subterminal area nana Dorsal vestiture fine, of hair or narrow flattened scales; apex of fore wing not specially darkened ( Titya) 2 2. Ground light brown; outer margin strongly scalloped in male, at least with hair-tufts at tips of veins in female 3 Ground dark gray, with fine, closely paired ordinary lines, thorax with contrasting white shoulders primitiva 3. The group of four pale pm. lines rather evenly spaced at costa; median area below cell not darkened, or somewhat darkened just beyond the antemedial line only ; male with pale cell . . mexicana The second line of the group of four obsolescent, the outermost curving in sharply to costa and fusing with the third; median area below cell much darkened in both sexes, and the veins (especially Mi and M 3 ) accented with blackish synoecura FORBES: LEPIDOPTERA OF BARRO COLORADO 293 Tolype nana Druce ? Phalaena Bombyx silveria Cr., Pap. Exot., 4, 134, 359: B, C, 1782. Echedorus nanus Dr., Biol. Centr. Am., Lep. Het., 1. 212, 22: 16 9 , 1887. Also figured: Seitz, 79: e6 d\ 5 9 . The female is rounder-winged and the dorsal half of the median area is contrasting, dark brown, usually enclosing a couple of tawny spots. T. lemoulti Schaus from Guiana has been mixed with this, but is larger, more buffy, with blackish apical shade less extensive, though contrast- ing, and the female lacks the contrasting brown median area. A few males in the National Museum from the Upper Amazons are inter- mediate and the difference may be only racial. Draudt thinks this may be the silveria of Cramer, but the figure of the latter looks to me more like T. poggei Schs. Dec. 5 (Bts.) Ranges north to Mexico. Tolype primitiva Walker Poecilocampa primitiva Wlk., List Lep. Ins. Br. Mus., 6, 1476, 1855. T. taruda Schaus, Proc. U. S. Nat. Mus., 29, 318, 1906. Figured: Seitz, 80: c5. Female much larger and rounder-winged than male. Costa-Lima reports the closely related T. proximo, as feeding on plum, pear and almost all kinds of acacias (from Mabilde). Dec. 5 cf , 27 9 , July 11 (Scr.); Lancetilla, Honduras, May (Bts.). Ranges to Guiana and the Amazons. Dyar reports T. synoecura Dy. from the Canal Zone, and the N. M. has specimens collected by Zetek. The types were from Mexico. The larvae are social in a hanging, pod-like nest, the cocoons formed in the nest. Larva cylindrical, mixed gray and brown, with a mixture of soft brown and stiff black-tipped hairs, the latter presumably stinging; food Terminalia buceras. He also reported T. mexicana H. S. from the Zone, but I could not verify the specimen. The larvae suggest these two species should be aberrant Malacosomas, but the pattern, vena- tion and other conventional characters agree with Tolype, group Titya. Artace Walker A minor variant of Tolype, differing most conspicuously in its white color. (Venation, fig. 74). The larvae are similar to Tolype, but in the present species the transverse band is orange. 294 bulletin: museum of comparative zoology Artace cribraria Ljungh Cossus cribraria Ljungh, Vet. Akad. Handl., 1825, 348, 2: C. Artace punctistriga Wlk., List Lep. Ins. Br. Mus., 6, 1491, 1855. Also figured: Beut., Bull. Am. Mus. Nat. Hist., 10, 19: 5; Holland, Moth Book, 12:5;Seitz, 82; 6d\ 5 9. Larva: Beut., Bull. Am. Mus. Nat. Hist., 10, 444, 1898; Mabilde, Borboletas do estado do R. G. do Sul, Porto Alegre, 1896; Costa-Lima, Terc. Cata- logo dos Ins. que vivem nas plantas do BrasiL, Rio Janeiro, 235, 1936. White with numerous black dots; palpus black and white, unlike A. rubripalpis, with which it has sometimes been confused. Larva on wild cherry, oak and peach (U. S.) or Ivy (Brazil). Jan. 3 (Bts.) Feb. 16, '36 (Wood), Mar. 14, '33 and 19, '36 (A.M. N.H.), June 21, July 9 (Scr.), also reported by Dyar. Ranges from southern U. S. to Brazil. Euglyphis Hiibner (Clajihe, Hydrias, Ocha, Nesara) Palpi much longer than in the preceding genera, beak4ike; scaling of fore wing almost always with an under layer of trifid or quadrifid scales, more or less overlaid with simpler ones, some of which may be attached with their length oblique to the axis of the wing, varying much from species to species. Thorax with a small metallic posterior tuft, some- times buried in the general loose hair. (Venation fig. 71). Larvae flattened, reported from various plants; Costa Lima notes deusta on canella branca (Psychotria), ogenes on aroeira (Lithraea), jasmine, branquilho (Sebastiania), canelleira do matto and other plants; rivulosa on avocado. A strictly neotropical genus of some 350 species. General characters are slight, but the species may be grouped by the wing scaling. The following is, I believe the first key ever attempted. 1. Thorax and inner margin of fore wing strongly contrasting with middle part of wing 2 Thorax and inner margin of fore wing not contrasting 3 2. Thorax and inner margin whitish and pale brown, the disc black- ish thyatira Thorax and inner margin black, the disc brown vittabunda FORBES: LEPIDOPTERA OF BARRO COLORADO 295 3. Overscaling, at least out to antemedial line, blunt-ended, spatu- late or strap-shaped, decumbent 4 Overscaling not represented as such, but in the form of many smooth-edged erect scales mixed with the normal long-toothed ones marginata 4. Costa of hind wing deeply dentate in male (fig. 75), less so in female ; overscaling narrow, strap-shaped, dense in outer part of wing, roughly parallel to direction of veins modesta Costa of hind wing with a large broad lobe, supported by second humeral vein, scaling normal (with moderately dentate under scales, and broad strap-shaped and narrow-dentate over- scales) 5 Hind wing with costa even, or a little waved in male, not dentate; over-scaling normally oblique, crossing vein A on a strong slant or even transversely, broader and imbricated 6 5. Ante- and postmedial lines pale, even and nearly straight, the other markings obscure sigurda Ante- and postmedial lines waved and less oblique, also with a double series of whitish st. spots at middle of outer margin . . . definita 6. Pm. as well as st. line deeply waved, the former extended in in long lines on veins, the latter with teeth between veins much longer than distance between veins; brown maria Pm. line, at least, moderately sinuate and waved, when visible . . 7 7. St. line deeply and regularly scalloped; major part of wing over- laid with obliquely placed hair-scales; general effect greenish. . . submarginalis St. line when distinct not much more deeply waved than pm. ; ground brown or buff 8 8. Antemedial line evenly excurved and not or only slightly waved, double, forming the outer boundary of a usually contrasting dark brown or buff base ; outer markings less conspicuous .... 9 Antemedial line moderately waved, much like postmedial, the basal area not contrasting 11 9. Median area narrow (1-5 length of wing), varying from cream white to brownish, the double pm. line almost as strong as the am. and cutting it off sharply on outer side discorica Median area broad, the pm. line weak, so that it gradually shades into the vaguely marked outer area 10 296 bulletin: museum of comparative zoology 10. Am. line hardly retracted at fold; base black-brown, the inner side of the am. lines defined by a narrow luteous line, and pale patch over fork of Cu when present essentially independent of it. rivulosa Am. line sharply retracted in fold, often interrupted on A; pre- ceded by an extensive pale patch which gradually narrows to costa; smaller and paler larunda 11. Disc of wing heavily shaded with white, giving a rather violet effect (scaling of inner border of narrower scales, though not strikingly so) rundala White scaling, when present confined to fine markings on ordinary lines and along veins 12 12. D.d. represented by two separate black raised dots; ground of both wings buff (Nesara) 13 D.d. single, when black; ground darker 14 13. Special st. spot in cell Mi of male bright tawny; ground duller, dark costal markings of hind wing extending to Mi . . . caramina Special st. spot in cell Mi of fore wing deep brown in male; the ground bright straw like most of hind wing; costal dark marks of hind wing extending only down to R casada 14. Thorax and fore wing a sort of dirty buff, the hind wing pale brown; veins of fore wing finely pale, lines pale and double, with some darker shading defining them lyso Thorax and both wings gray or brown, the ordinary lines usually single and dark, though often defined by pale dots on veins. . 15 15. Fore wing overlaid with slender pale yellow scales, giving a frosted effect; the yellow-white on ordinary lines well marked; costal part of hind wing with the same pattern 16 Fore wing mottled with dull brown, without slender pale scaling; the ordinary lines obscure, dark, or partly dotted with yellow- white; entire hind wing with diffuse markings 18 16. Pale on veins in the form of separate dots; hind wing with st. markings obscure 17 Pale on veins continuous or nearly so, often extending in teeth on veins, and the am. and pm. lines typically connected by a pale line on Cu; d.d. obscure; st. dots of hind wing conspicuously pale char ax 17. Darker, the dorsal half of hind wing redder; fore wing with d.d. obscure, slightly darker; st. markings regular melancholica FORBES: LEPIDOPTERA OF BARRO COLORADO 297 Paler, the dorsal half of hind wing dull brown; fore wing with conspicuous black d.d. (rarely small, but always contrasting); st. retracted at cell M 2 , and marked by a contrasting blackish spot or shade amathunia 18. Discal dot obscure, st. a fairly regular series of black dots (though tending to omit Mi) ; no whitish shades sobrina Diseal dot conspicuous, sometimes very large; st. dots small, in a whitish shade, tending to be ocellate as far as Mi, especially in the female, then abruptly larger and with little or no white attenuata Group I: Overscaling of fore wing of two sizes, that toward the inner margin definitely finer than the rest; R\ slanting up to Sc at an angle of about 30°; 1st hum. of hind wing long, reaching to about opposite end of cell; hind wing evenly rounded or nearly so (Euglyphis). EUGLYPHIS THYATIRA DrilCe cf Lasiocampa thyatira Dr., Biol. Centr. Am., Lep. Het., 1, 203, 22: 2, 1887. 9 Claphe albiplaga Schaus, Proc. U. S. Nat. Mus., 29, 301, 1906. E. t. form taminata Draudt in Seitz, Macrolep. World, 6, 601, 83: hi, 1927. Figured: Seitz, 83: g6 (typical), hi {taminata). Blackish, with two small and a large apical cream costal patches and three partly fused dorsal ones. Female with spots small, white, blurred; a large elongate ocellate elliptical black discal dot with white center. Yar. taminata has a light gray thorax, and the white at middle of costa is a dash 3 times as long as wide. It is perhaps the southern race. Dec. 27, Mar. 23 (Bts.) Mar. 1, '33 (A.M.N.H.), June 22, July 6, '40 (Scr.). Lancetilla, Honduras (Bts.) to Guiana. Var. taminata was described from Colombia. Euglyphis vittabunda Dyar Claphe vittabunda Dyar, Proc. U. S. Nat. Mus., 47, 222, 1914. Superficially, this species is extremely close to C. mama Schs., from Brazil, (fig. 83), but the genitalia (fig. 82) are of a different type. There is also an undescribed species even closer to vittabunda (fig. 84), but it is a little coarser looking, the hind wing much redder, and the genitalia have stouter costal hooks of the valves, the uncus has a smaller median portion and the lateral spinules on the tip of the aed- oeagus are vestigial. It is figured in Seitz (83: g2 cT, 1 9 ) as marna, which in fact differs from both in having the pm. line continuous 298 bulletin: museum of comparative zoology though somewhat sinuous where the black patch begins. In vitta- bunda and the new species there is a definite break. Oct. -May (see diagram). Described from the Canal Zone, and not known authentically from elsewhere. EUGLYPHIS RUNDALA SchaUS Claphe rundala Schs., Proc. U. S. Nat. Mus., 29, 304, 1906. Figured: Seitz, 83: i2. Finer scaling of inner margin hardly distinct from the rest. Male with postmedial line on costal half of fore wing represented by two diffuse whitish lines, the inner only moderately excurved, but the outer swinging almost out to the st. Female with this whole region suffused with violet gray. In the closely related E. laronia Druce, which is regional, only the inner pm. line is present. Abundant (see diagram). Guatemala (Nat. Mus.) to Guiana (type) and Middle Amazons (Cornell). Group II: Similar, except that the overscaling of the ivhole wing is a similar mixture of dentate and strap-shaped scales; 1st hum. of hind wing generally shorter, especially in melancholica and charax, but overlapping base of Sc. [Euglyphis submarginalis Walker Eriogaster submarginalis Wlk., List Lep. Ins. Br. Mus., 35, 1948, 1866. Hydrias praxithea Dr., Ann. Mag. Nat. Hist. (6) 13, 181, 1894; Biol., 87: 1. Also figured: Seitz, 82: e3 d\ 2 9 . Metallic crests coppery, also present on abdomen. The abundant fine yellow hair on a gray base gives an olive effect. Mexico to Brazil, reported from the Canal Zone by Dyar. Larva (U. S. Nat. Mus.) of the "lappet type," quite unlike the nor- mal Malacosoma group, but as in Tolype. Pattern speckly in shades of wood brown, with a tendency to longitudinal striping; side tufts strong, pale; pale transverse dorsal tufts on meso- and metathorax, a thick tuft on 1st segment of abdomen, transverse tufts on 2 and 3 with velvety black patches before them ; 4 to 8 each with 3 (dorsal and subdorsal) tufts, the ones on 5 larger, with a dark patch behind them. Cocoon flat, silken, pupa pubescent.] Dyar also reports E. maria Schs., a brown species with pm. as well as st. line very deeply scalloped, and the amount of overscaling much less. FORBES: LEPIDOPTERA OF BARRO COLORADO 299 Euglyphis discorica Dyar Claphe discorica Dyar, Proc. U. S. Nat. Mus., 47, 222, 1914. ? Gastropacha obtusa H.-S., Samml. aussereur. Schm., fig. 471, 1856. The narrow pale median area with large black discal spot on its inner border is distinctive. The area varies from cream white to pale brown, only a little lighter than the ground. Nov. 27 (Bts.) Mar. 13 (A.M.N.H.), July 3, 21, 25 (Scr.), males; described from Taboga Id. (Dyar) and Guiana (H.-S.) Euglyphis rivulosa Miischler Hydrias rivulosa Moch., Verh. k. k. zool.-bot. Ges. Wien, 27, 675, 10: 39, 1878; Lep. Cat. 73, 86, 1936. Also figured: Seitz, 84: f3 (much too dull). Early Stages: Jorgensen, D.E.Z., Iris, 46, 58, 1932. There are several extremely close species in this group. I have a few specimens from the Guianas, whose genitalia agree with the Barro Colorado ones (fig. 79), but none from Paramaribo. The species from southern Brazil (which I take to be maha Schs., fig. 80) has prac- tically the same pattern in the male, but the antemedial line is more deeply dentate at A, the genitalia are distinct, and the basal area in the female is extended far out in the middle. In the present lot the female is much like the male in pattern, though larger and heavier as usual. Both this species and maha are dimorphic, the male frequently having an oval cream patch on the brown basal area. Larva bark-like, pale yellowish gray, with a red longitudinal stripe, blackish side-spots and other faint yellowish stripes; lappet-hairs gray; under side red with black borders. On Lauraceae. (I am not at all sure this is the true rivulosa; from the locality it is more likely to be maha, but rivulosa is doubtless • similar). Common (see diagram). Described from Dutch Guiana, other lo- calities doubtful from confusion with related species. E. larunda Dr. (Biol. 22 : 7, as laronia) is regional and will doubtless be taken on the island. It is smaller and more delicately marked than rivularis, the female light gray, much like the male; and the male valves lack the tooth at the base of the costal hook (fig. 81). Euglyphis charax Druce Hydrias charax Dr., Biol. Centr. Am., Lep. Het,, 2, 433, 86: 20, 1897; Eugly- phis c. Collier, Lep. Cat., 73, 72. 1936. Also figured: Seitz, 83: i6. 300 bulletin: museum of comparative zoology The amount of cream-white on the veins varies, — sometimes the lines are not connected below the cell as in the type and present specimen. Dec. 8 (Bts.) Guatemala to Colombia (Nat. Mus.) EUGLYPHIS AMATHURIA DruCC Hydrias amathuria Dr., Proc. Zool. Soc. London, 1890, 503; Euglyphis a. Collier, Lep. Cat., 73, 69, 1936. Metallic crest high, continued on much of abdomen; overscaling rather slender, yellowish, abundant; am. and pm. lines marked mostly by the series of yellow dots, but st. with well-marked preceding black- ish shades, the subcostal one and one in cell Mi heavy. Common, Jan. -Apr. (see diagram). Costa Rica to Ecuador. Dyar reports E. mclancholica Btl. from the Canal Zone. It is more olive, without the conspicuous discal dot, and the hind wing is redder. The A.M.N. H. party took it at Chiriqui. Euglyphis lyso Druce Hydrias lyso Dr., Biol. Centr. Am., Lep. Het.,- 2, 435, 87: 4, 1897. Claphe inflata Schs., Ann. Mag. Nat. Hist. (8) 7, 371, 1911. Also figured: Seitz, 84: h4 (lyso 9 ); 85: il (inflata) Terminal lunules white, contrasting; discal dot conspicuous and single in the present male, double in original figure of female; a group of three st. black spots at costa. Female with pattern more blurred and lacking the white terminal lunules. Apr. 23 (Fried.), July 1 (Scr.). Costa Rica to Brazil. This is the species standing as lyso in the Nat. Mus. and agrees with the type of inflata. The original figure of female lyso looks different. Group III: Identical with group II, except that the costa is broadly lobed over the tip of 2d hum.; 1st hum. relatively short, scaling soft and fine. Euglyphis definita Schaus Claphe definita Sch., Ann. Mag. Nat. Hist. (8) 6, 563-4, 1910; Euglyphis d. Seitz, 617. Ground dull brown, markings a little blurred, m. area a little paler, except for a very vague longitudinal streak through end of cell. Costal part of hind wing darker, but not otherwise contrasting. Feb. 3, cf (Bts.); Dec. 4 (Bts.), Feb. 17 (Fried.) 9 's. Described from Costa Rica. FORBES: LEPIDOPTERA OF BARRO COLORADO 301 EUGLYPHIS SIGURDA SchaUS Claphe sigurda Schs., Ann. Mag. Nat. Hist. (8) 6, 570, 1910; Euglyphis s. Seitz, p. 618. Color and soft appearance as in the preceding; lines fine, almost white, slightly converging to inner margin, the pm. line acutely curved about between R 3 and R 4 . St. marks barely traceable. The type is male, the present specimens female, but I have no doubt of the determination. Dec. 27 (Bts.) Mar. 22 (Fried.) Described from Costa Rica. Group IV: Ri still running across to Sc at an angle of about 30°; scaling and fore wing as before; hind wing with strong basal lobe, supported by a short and heavily bifurcated 1st hum., outer part of costa deeply scalloped, R and Mi arising widely separated. Euglyphis modesta Druce Lasiocarnpa modesta Dr., Biol. Centr. Am., Lep. Het., 1,203, 1887; Phyllodesma ? to. Kby., Cat. Lep. Het., 825, 1892; Epicnaptera ? to. Closs, Int. Ent. Zeit., 7, 179, 1915; Euglyphis to. Ddt. in Seitz, p. 618. 1928. The doubtful references to Gastropachine genera are on account of the odd wing-form; the venation (fig. 75) is perfectly normal for Eugly- phis, except for the development of one of the usually minute anterior branches of 1st hum. into a main fork. Wood-brown, the ordinary lines blackish and waved, finely and partly defined with white. Median area sometimes contrastingly deep brown, as in Malacosoma disstria f. sylvatica. Oct. 8 to Mar. 6 (see diagram). Costa Rica to southern Brazil (Cornell). Group V: Ri crossing to Sc at a much steeper angle, about 45°, and im- mediately becoming extremely close to Sc; hind wing with 1st hum. very short, extending less than half length of cell and barely overlapping base of 2d hum. ; Sc arising almost at apex of cell and R long-stalked with Mi. Scaling with no distinction in position of under and over scales, but with a proportion of scales erect and smooth-edged, without the usual marginal teeth (Nesara in part). Euglyphis marginata Schaus Ocha marginata Schs., Proc. Zool. Soc. London, 1894, 239. Ocha libnites Dr., Biol. Centr. Am., Lep. Het., 2, 436, 87: 8, 1897. 9 Claphe falsifica Dgn., Het. nouv. Am. Sud, 22, 19, 1923. Claphe jeba Schs., Ann. Mag. Nat. Hist., (8) 6, 573, 1910. Also figured: Seitz, 85: a7 d\ 8 9 ,kl0 9 (falsifica). 302 bulletin: museum of comparative zoology Brown, the pm. line double, arched far out, almost to st. line, but abruptly retracted in cell Mi; st. lunulate, black in a violet gray shade, which is stronger before and beyond, and fills the lunules. In typical marginata (libnites) there is a little darkening of cell Mi from discal cell to pm. line and a slight basal dash in fold, but in var. jeba the pm. area is deep brown and the basal dash extends almost 1/3 length of wing. Both forms normally have an oval patch over cells M 2 and M 3 . Female umber brown, rather suffusing all the markings, the hind wing mouse gray. Falsified was based on its darkest condition. Abundant (see diagram). Mexico to Venezuela. Group VI: Ri of fore wing and 1st hum. of hind wing like group V; scaling normal, with fine over-scaling, the vestiture of thorax normally fine and strap-like; Sc arising well back from end of cell and R rarely stalked (Nesara). Dark species, the thoracic tuft lead-color. EUGLYPHIS SOBRINA SchaUS Claphe sobrina Schs., Ann. Mag. Nat. Hist., (8) 6, 570, 1910. Figured: Seitz, 84: i4. Effect of group II. Dull brown, the overscaling broad and deep giving only a vague mottled effect; crest confined to thorax. Lines blackish, rather punctiform and more or less defined by white dots, the st. plainer and more scalloped. Dec. 8-Apr. 10 (see diagram). Described from Costa Rica. EUGLYPHIS ATTENUATA SchaUS Claphe attenuata Schs., Ann. Mag. Nat. Hist., (8) 6, 572, 1910. Ocha falsa Schs., Proc. Zool. Soc. London, 1894, 238. Claphe palma Schs., Proc. U. S. Nat. Mus., 29, 316, 1906. Figured: Seitz, 85: k9 (attenuata), 8 (palma) The type form has a dark m. area and extremely large black discal dot, var. palma is lighter, warmer brown, with a blackish patch beyond cell, falsa is grayer, and the type had a minute discal dot, but others from southern Brazil have the large spot. I think the forms are not local but the grayer tint of southern specimens (falsa) may have some meaning. Common, Oct.-Apr. (see diagram). Costa Rica to southern Brazil. Pale species, the glossy thoracic tuft buff. FORBES: LEPIDOPTERA OF BARRO COLORADO 303 EUGLYPHIS CASADA SchaUS Ocha casada Schs., Ann. Mag. Nat. Hist., (8) 7, 372, 1911; Nesara c. Ddt. in Seitz, p. 619. Figured: Seitz, 85: e7. Ground ochre, the fore and hind wings similar in color, markings brown, contrasting, the most conspicuous a bar from inner pm. line to St., cut by the pale element of the outer pm. Mar. 13, 1936 (A.M.N.H.), also Chiriqui. Described from Costa Rica. Bates took a single female of this group (Dec. 11) which certainly does not belong to casada. I suspect it is E. (X.) earamina, of which he got males in Honduras. EUPTEROTID.E Head with tongue absolutely rudimentary, but palpi usually well developed; antennae in our species pectinate in both sexes. Body stout, with deep vestiture, tympanum absent. Wings (figs. 86-89, 92) with Cu apparently trifid (almost quadrifid in a few Old World Eupterotinae) ; radial system in our species (Apatelodinae) normally with R 2 stalked with 3 and R 4 with 5 , their stems normally more shortly stalked together, occasionally with R 2 and 3 completely united; hind wing with Sc rather closely parallel to cell near base, then gradually diverging and connected with cell by a cross vein. Frenulum in our species strong. Pattern complex, the antemedial and postmedial lines each represented by two lines or bands, which may be widely separated and may differ in behavior,— as in various other lower "Bombycine" families, such as the Bombycidae and Thyatiridae. Under side nor- mally with complex and sharply defined pattern ; inner margin of hind wing above normally with special markings and displayed at rest. Egg extremely flat, disc-like; caterpillar as in the Lasiocampidae, with much fine secondary hair and obscure warts; in the Epia group with spatulate scales mixed with the hair, and frequently with long pencils. Pupa smooth, with a ring of sculpture on the edge of each abdominal segment ; that of the Apatelodes group buried in the ground, unlike the residue of the Bombycoidea. In appearance there is considerable difference between the Euptero- tinae and Apatelodinae, . but it is difficult to find any simple formula to separate them; as a rule in the Eupterotinae the frenulum is weaker and in the radial system R 3 and 4 are stalked the farthest. In the New 304 bulletin: museum of comparative zoology World they are represented only by Preptos, with two species in Cen- tral America. The larvae are also closely similar, and quite unlike the nearly naked, humped or horned larva of the Bombycidae. Only Colla is reported to have a Bombycid-like larva. 1 . Even the row of fine dorsal hair-pencils of Apatelodes reappears in Preptos, though they are absent in the Old World Eupterotinae. The Apatelodinae are generally treated as limited to the New World, but "Andraca" albilunata, from eastern Asia, is a normal Apatelodine, perhaps even a species of Apatelodes, and Prismosticta and Panacela show some Apatelodine features. Of these three types only the larva of Panacela is known, — it is hairy, unlike the Bombycidae. Aside from the general references listed in the introduction, there has never been a revision of the subfamily. Key to Genera (after Schaus in Seitz) 1. R 4 of fore wing convex and closely parallel to costa, R 2 3 run- ning parallel to them, generally a simple vein (fig. 86) 2 R 4 of fore wing sinuous, R 2 and 3 generally forking immediately after their separation from R 4 and 5 (fig. 92) 6 2. Apex of fore wing rounded 3 Apex of fore wing marked 4 3. Cui of fore wing arising well before angle of cell; underscaling normal Epia Cui of fore wing close to angle of cell or connate with M 3 ; under scales with very slender bases bearing about 4 long spikes, like some species of Euglyphis Colla 4. Apex produced (fig. 87) Quentalia Apex merely right-angled (fig. 86) 5 5. Abdomen not extending beyond hind wing and without tufts. Anticla Abdomen extending beyond hind wing, and with tufts on both. Tarnphana 6. Apex acute; outer margin almost evenly rounded Zanola Apex usually a little blunted, outer margin sharply bent or angled just below vein Mi 7 7. Outer margin of fore wing scalloped on dorsal half, in particular with a distinct tooth at M 3 Olceclostera Outer margin even from M 2 to anal angle Apatelodes 1 Schade, Ent. Rundsch., 56, 65-67, 1939. FORBES: LEPIDOPTERA OF BARRO COLORADO 305 Epia Hiibner (Anthrocroca Boisduval, Hygrochroa Felder et al., not Hiibner 1 ) Wing-vestiture deep and soft, the under scaling only moderately toothed; colors darker, buff, brown or olive, (venation fig. 77). 1. Male with an olive costal triangle extending down to vein M 2 and contrasting with the brown general ground muscosa Male with the triangle when distinct extending down across M 3 ; the ground olive to bright green and not contrasting .... casnonia Epia muscosa Butler 9 Anthocroca muscosa Btl., Trans. Ent. Soc. London, 1878, 79, 3: 5; Biol., 1, 224; Kirby, Cat. Lep. Het.. 721, 1892. & A. cuneifera Btl., Trans. Ent. Soc. London, 1878, 79, 3: 4; Biol., 1, 224 (pr. tf). Also figured: Seitz, 89: a2 d", 1 9 . Male with ground two shades of warm brown; an olive costal tri- angle, shades near margin, and dark brown pm. line most conspicuous. Female strikingly different, the olive markings confused and hind wing much redder than fore wing. Common; flight scattering, after mid-December (see diagram). Guatemala to southern Brazil. Epia casnonia Druce ranges from Guatemala to Peru. Northern males are dull olive with violet-gray shades, and the costal triangle rather distinctly set off; southern ones are almost evenly olive green (very bright when fresh), and the median area has fine widely sepa- rated dark lines not enclosing a triangle ; the female is smaller but not easily distinguished from E. muscosa. Both forms were taken by Bates at Lancetilla, Honduras, and will doubtless occur on Barro Colorado Id. Colla Walker (Prismoptera Butler) This genus has a remarkable superficial likeness to the old world Bombycid genus Ocinara, which has a good deal to do with the ten- dency to combine the Apatelodinae and Bombycidae. In fact vena- tion (fig. 78) and scaling are quite different, and the likeness is certainly parallelism. The ground is generally white, shaded with light gray, and so thinly scaled as to expose the iridescent membrane. Under-scaling reduced to branched hairs. 1 Hygrochroa Hiibner was based on a true Apatelodes and a European geometer; the name is now used for the geometer. 306 bulletin: museum of comparative zoology Larva of C. jehlii Schade nearly naked, humped with horns on 2d and 8th abdominal segments; on Ficus (Schade, I.e.) Pupa of C. rhodope Dru. according to Druce dark brown, enclosed in a silvery gray silky cocoon. COLLA COELESTIS Schaus C. coelestis Schs., Ann. Mag. Nat. Hist., (8) 6, 414, 1910. Figured: Seitz, 89: b8. Small and noticeably round-winged, the wings rather strongly marked with light gray; thorax white, the posterior tuft contrasting, gray. Jan. 27 (Bts.), June 24 (Fried.). Described from Costa Rica. Quentalia Schaus (Carihara auct., not Walker) Similar to Apatelodes, with the same marked apex and bent or angled outer margin, but with the stem of R 2 and 3 closely parallel to R 4 for some distance beyond the forking of R 5 , and both convex to costa (fig. 87); frenulum short but functional. A good sized genus, but with the species characters not well under- stood. The few species yet known from the Island however are clearly defined. 1. Discal lunule of upper side of fore wing a narrow oblique bar of curly raised scales, about as high as the cell; outer pm. line sin- uous and excurved over M 3 ; discal lunule of hind wing below in our species with white scales .veca Discal lunule of upper side of fore wing represented by two widely separated black dots; outer line not convex over M 2 , normally concave to just above M 3 ; discal linule of hind wing below dark . .2 2. Base of abdomen with a contrasting transverse dark (brown or olive) band; outer pm. evenly concave from costa to M 3 , forming the outer boundary of a triangular dark patch in both sexes . . numalia Base of abdomen with two small brown tufts only; marking much less definite in male, the outer pm. whitish, obscure and nearly straight above, though scalloped below M 3 ; female with blurred markings ephonia FORBES: LEPIDOPTERA OF BARRO COLORADO 307 Quentalia veca Druce Carthara veca Dr., Biol. Centr. Am., Lep. Het., 1, 224, 23: 2l"d\ 22 9 , 1887. Q. chromatid Schs. in Seitz, Macrolep. World, 6, 690, 89: il tf 1 , 2 9 , 1929. Carthara reissi Mssn. in Stubel, Reisen in Sudamerika, Lep., 132, 5: 6, 1890. Also figured: Seitz, 89: h9 d\ Fore wing squarer than in the other species, the outer margin nearly vertical from apex to middle angle, especially in male; pm. line double, the inner line dark and waved, the outer widely separated at costa, closest opposite cell, dark followed by pale, concave toward^ costa and waved below, — the am. elements similar in reverse order.' Ground color variable, typically deep indian red, shaded with red- brown, in var. chromatid Schs., deep olive brown, frequently frosted with white, in the var. which the Nat. Mus. takes to be reissi 1 with a contrasting olive wedge between M 3 and Cui, becoming diffuse to margin. The majority of the present lot are of v. chromatid, with a fair block of the type coloring, one reissi and several transitional specimens, in- cluding several with the reissi wedge on the chromana ground. The single female is of v. chromana. Common, with principal flight in Nov.-Dec. (see diagram). Ranges to Costa Rica and Ecuador. Quentalia numalia Schaus and Heinrich Q. numalia S. & H. in Seitz' Macrolep. World, 6, 684, 89; fl, 1929. The dark costal triangle is the upper half (down to M 3 ) of the double pm. line with the space between, filled with gray in its upper half and below with brown. In this group there are many neotropical species absolutely identical in markings but with strikingly distinct genitalia. Names will be a little uncertain till types of the older names have been examined, but we figure a few that we believe are correctly named (figs. 90 numalia 91 surynorta, 85 an undescribed species common in southern Brazil). The last sternite is easily uncovered by denuding and is distinctive of each species, — that of numalia has two long asymmetrical terminal spikes, its ninth tergite has two pairs of marginal points, about like surynorta from farther north, and the lower half of the valve simply tapering and short, with terminal bristles (subterminal at a sharp bend in surynorta). 1 The original figure is paler than any specimens I have seen of veca, a common fault in hand-coloring. 308 bulletin: museum of comparative zoology Jan. 9, Feb. 6 (Fried.) Chiriqui (A.M.N.H.). Costa Rica (tvpe and C.U.) This species would have been included in the Biologia conception of drepanoides (p. 225), but they had no material from Panama. The variation in color that they mention probably occurs in each of the species, and is striking in the series of surynorta collected by Bates in Honduras. QUENTALIA EPHONIA Stoll Phalaena Bombyx ephonia Stoll in Cr., Suppl. Pap. Exot., 96, 19:5 (larva and pupa); 159, 35: 6, 1791. Carthara lividia Dr., Biol. Centr. Am., Lep. Het., 1, 225, 23: 23 .■• michorta 1, Rofree; scaling smooth 386 bulletin: museum of comparative zoology Natada fusca Druce Trabala ? fusca Dr., Biol. Centr. Am., Lep. Het., 1, 207, 22: 11, 1887. Perola salta Dr., Ann. Mag. Nat. Hist. (7) 5, 512, 1900; Dyar in Seitz, Macro- lep. World, 1124, pr. syn. Ground varying from luteous to mouse gray, the ordinary lines with the dark elements prominent in the first, the pale in the second case; converging and almost meeting at costa before apex. Abundant (see diagram). Mexico to Venezuela. Natada subpectinata Dyar N. subpectinata Dyar, Proc. U. S. Nat. Mus., 29, 381, 1905. N. urichia Schs., Proc. Ent. Soc. Wash., 26, 180, 1924; Dyar in Seitz,1124, pr. syn. Biology: Freeman, Rept. Dept. Agr. T'dad, & Tobago, 1924, 22, 1925 (Rev. Applied Ent., 13, 493, 1925). Much smaller than N. fusca, the fore wing wholly of reddish tints. Base of M lost, represented by a faint fold, well below middle of mdcv. N. nucea Dgn. is similar but has much finer pure black lines, the st. somewhat sinuous. The present specimens are slightly abnormal, having more nearly the color of daona (Seitz, 165: g3). Dec. 5, 9, 21 (Bts.) Feb. 7 (Fried.) Dutch Guiana (type). Natada nindla Dyar N. nindla Dyar, Proc. U. S. Nat. Mus., 42, 96, 1912. Figured: Seitz, 165: il. Dull brown, head and thorax paler, basal half of wing vaguely darker. Fore wing with traces of a blackish pm. band from near middle of wing to inner margin and a curved blackish line from shortly before apex to well below middle of outer margin. Aug. 8, 1940 2 d* (Sc.,). Described from Costa Rica. 2, R 2 stalked; fore wing water-lined. Natada incandescens Dyar N. incandescens Dyar, Proc. U. S. Nat. Mus., 29, 380, 1906. Figured: Seitz, 165: h5. Warmer brown than the following; the fore wing with some violet gloss, and vague suggestions of a darker base and sinuous pm. band. Water-banding irregular. Oct. 18-19 (Bts.) May 6- June 6 (Fried.). Ranges to Guiana and the Amazons. FORBES: LEPIDOPTERA OF BARRO COLORADO 387 Natada michorta Dyar AT. michorta Dyar, Proc. U. S. Nat. Mus., 42, 96, 1912. Figured: Seitz, 165: i4. With very sparse single black scales, otherwise immaculate or with a faint trace of the dark st. spot of the following. Principal flight in Dec. (see diagram) but with scattering specimens in Mar-Apr., perhaps indicating a second brood. Ranges to Guate- mala. Natada lucens dognini Dyar (Amydona lucens Wlk., List Lep. Ins. Br. Mus., 5, 1111, 1855). N. dognini Dyar, Proc. U. S. Nat. Mus., 29, 379, 1906; Dyar in Seitz, 1125, race lucens. Figured: Seitz, 165: i6. Very like the North American Sisyrosea textula, but larger and darker. The Seitz figure is very bad, the wings too dark, thorax too light, tint too dull (should have a violet tint) and water-lining not shown. Scattering, with perhaps some concentration in Feb. -Mar. (see dia- gram). Ariz, to Brazil. Perola Walker Similar to Natada, except for the stalked Cu x and 2 of fore wing (fig. 119); R 2 connate or slightly separate; R 5 separate; hind wing with base of M attached far above middle of mdcv. 1. Fore wing dull gray, immaculate repehta Fore wing yellow with buff -brown markings and often pink shades 2 2. Postmedial line double toward costa, pink shading strong, basal half of fore wing below fold contrastingly pale .villosipes Postmedial line single, marked by a brown spot in fold; pink limited to body, slight; inner margin of fore wing concolorous. . .sericea Perola villosipes Walker Trabala villosipes Wlk., List Lep. Ins. Br. Mus., 32, 555, 1865. Phocoderma v. Kby, Syn. Cat. Lep. Het., 538, 1892. Perola v. Dyar, Jour. N. Y. Ent. Soc, 6, 238, 1898, etc. Not figured. Fore wing with brown streaks on veins, especially above fold and before outer pm. line, the inner pm. curving sharply in at end of cell. 388 bulletin: museum of comparative zoology and running into the streak on R; outer pm. irregularly curved and dentate below cell. Four c?'s May 1, 2 (Fried.) 1 9 May 26 (Fried.) Ranges to Guiana. Perola sericea Moschler Asbolia sericea Msch., Verh.z-b. Ges. Wien, 27, 671, 10: 36, 1878. Pseudasbolia s., Kby., Syn. Cat. Lep. Het., 877, 1892; Perola s. Dyar, Jour. N. Y. Ent. Soc, 6, 238, 1898, etc. Also figured: Seitz, 166: fl. Yellower and a little smaller than the preceding species, the vein- streaks more distinct toward inner margin, but not distinct below cell; pm. obscure or interrupted beyond lower angle of cell, not dentate. Oct.-Nov. (Bts.) (see diagram). Two rubbed specimens taken by Friedman May 17, may represent a third species. Mexico to Guiana. Perola repetita Druce P. repetita Dr., Ann. Mag. Nat. Hist., (7) 5, 512, 1900. Figured: Seitz, 166: b2. Scaling of two shades of fuscous, partly with white tips, with a hint of the water-lining of the second group of Natada. Immaculate. Common (see diagram), chief flights Oct.-Nov. and Mar.-Apr. Mexico to Guiana and Bolivia. Palaeophobetron Dyar Similar to Epiperola, but frontal tuft shorter, and palpi much shorter, hardly exceeding the front. R 5 strongly stalked. Habitus distinct, the pm. line irregular or obscure and wings more pointed than Epiperola. Dyar finally sunk this genus in Epiperola, but the general appear- ance is distinct, and I suspect it may really be closer to Phobetron than to Epiperola. 1. Ground bright buff, marked with brown, coal black and some white perornata Luteous, shaded with blackish along costa and fold, with a large oval white spot on middle of A cinereum Palaeophobetron perornata Dyar Epiperola perornata Dyar, Proc. U. S. Nat. Mus., 29, 383, 1906. Figured: Seitz, 166: a4. FORBES: LEPIDOPTERA OF BARRO COLORADO 389 Fore wing with markings complex, the most distinctive being large rounded buff patches at apex and opposite lower angle of cell and a fine irregular pm. white line, preceded with black and followed with dark brown. Female with blunter wings than male. Dyar never placed this species in Palaeophobetron, even when he recognized the genus as distinct, but it shows the essential features, and is even nearer to Phobetron in pattern than the other species. The larva will settle the matter. Common, obviously double-brooded, only three specimens being taken between Nov. 8 and May 6 (see diagram). Costa Rica to Guiana. Palaeophobetron cinereum spec. nov. Cream, marked and shaded with gray. Head paler, the front darker and upper side of the flattened palpi dark brown, contrasting; thorax shading into light brown laterally; abdomen light brown, legs shaded with brown, the fore tibia with a strong fringe of blackish tipped hair scales on outer side, ending in a triangular apical black tuft which extends more than half length of tarsus. Fore wing irregularly shaded with blackish, especially along costa and very strongly along veins, leaving the costal space contrastingly pale; vague pm. and st. blackish bars extending down a short distance from costa, strongly accented on veins, vague smoky shades near base and beyond middle of cell and a gray chevron over discal bar; outer part of wing with a semicircular gray line from beyond end of cell almost out to margin, curving back and ending on Cu 2 just before anal angle; a strong black- ish shade along 1st A from base to outer margin, giving off a branch on its lower side to inner margin at 2/3, generally fading out above and below, but sharply defined below by the upper edge of an ovate shin- ing cream spot lying on middle of 2d A, and a small st. spot on 2dA, both of these spots more clearly defined above than below; fringe dark brown, contrasting, with blackish terminal line and middle and terminal lines in the fringe; hind wing cream, shading into light brown toward inner margin, the veins dark, especially Cu with its forks; and fringe as on fore wing. Barro Colorado Id., C. Z. Panama, holotype Dec. 31, 1934 (Bates) in M.C.Z., paratype Jan. 3, 1935, deposited in Cornell University collection. This species is related to P. arcuata Dr. (Biol., SS: 9; Seitz, 166: a7) but is much paler, with relatively much larger cream spot on 2d A. 390 bulletin: museum of comparative zoology Epiperola Dyar Similar to Perola except for the loss of the upper spurs of hind tibia. This genus (or section) is obviously connected with Perola, and has the same head characters. I have not examined E. monochroma struc- turally and it may be a Palaeophobetron, but I think not. The pm. line is single, oblique and pale as in various Natada and Perola; R 5 almost always free. 1. Ground blackish, the pale pm. line running to apex vafera Ground light gray, the pm. line from well before apex . albimarginata Ground cream, mottled, the line denned with light gray paida Immaculate brownish ochreous monochroma Epiperola albimarginata Kaye Sisyrosea albimarginata Kaye, Trans. Ent. Soc. London, 1901, 158; Epiperola a., Dyar, Proc. U. S. Nat. Mus., 29, 383, 1906. E. argentilinea Gaede, D.E.Z. Iris, 30, 208, 1916; Dyar in Seitz, 1126, pr. syn. Light gray with scattered black scales, the pm. line somewhat de- fined with brown, and dark basal line in fringe. Oct. 30 (Bts.) Feb. 24 (Fried.) Mar. 3 (Fried.), 12-18 (A.M.N.H.) Ranges to Guiana and Brazil. Epiperola paida Dyar E. paida Dyar, Proc. U. S. Nat. Mus., 42, 97, 1912. Perola osseata Schs., Proc. U. S. Nat.- Mus., 57, 148, 1920; Dyar in Seitz, 1126, pr. syn. Figured: Seitz, 165: k3 (unrecognizable if meant for this at all). R 5 short-stalked in 3 out of 4 specimens; ground paler than the pre- ceding, with shade before the pm. line broad and irregular and discal dot strong and black. Oct. 19, 24, Nov. 15, Dec. 13 (Bts.). Ranges to Guatemala. Epiperola vafera Druce Perola vafera Dr., Ann. Mag. Nat. Hist., (7) 5, 512, 1900. Palaeophobetron v., Dyar, Proc. U. S. Nat. Mus., 29, 382, 1906. Epiperola v., Dyar in Seitz, 1126. Perola gaya Schs., Proc. U. S. Nat. Mus., 57, 148, 1920; Seitz, I.e. pr. syn. Figured: Seitz, 165: k7. FORBES: LEPIDOPTERA OF BARRO COLORADO 391 Dark fuscous, the line fine, luteous, slightly powdery, faintly de- fined with darker. This is a short-winged, heavy, Natada-like species, and I see no resemblance to Paleophobetron. Dec. 13 (Bts.) Mexico to Amazons. Dyar also reports E. monochroma Dyar; it was described from further west in Panama. Dichromapteryx Dyar Similar to Prolimacodes in build and structure; differing only in the small size and distinctive pattern, the wing being practically bisected by a straight pale shade. I cannot see the antennal difference indi- cated by Dyar. Dichromapteryx didyma Dyar D. didyma Dyar, Proc. U. S. Nat. Mus., 42, 99, 1912. Distinguished from related species by the contrasting coppery dorsal crest and apical shade. Series (see diagram). Described from Costa Rica. Prolimacodes Schaus (Eulimacodes auct. not Moschler) This is the only Neotropical genus so far as I know belonging with- out doubt to the smooth Eucleids, though plenty of possibly related genera have unknown larvae. Antenna simple, with a double series of small ventral dentations, rather less than truly serrate; palpi obliquely upturned to middle of front. Fore wing with upper angle of cell somewhat extended, M attached to near lower end of mdcv. or even opposite M 2 ; hind wing with Sc and R distinctly separated, connected by the "cross- vein" ; upper angle of cell rather retracted. Larva of the North American P. scapha smooth, with a strong longi- tudinal subdorsal crest, which rises almost to an angle at middle of body. Lateral crest absent (shown by earlier stages to be practically fused with subdorsal one); abdominal spiracles all alike and in line. Green, the dorsum brown, contrasting. Food various trees and shrubs. Hopp has published a key to the species (D.E.Z. Iris, 41, 174). 1. Body long, male with half its length projecting beyond abdomen; brown patch of fore wing truncate-triangular, extending to 2d A and very finely or imperfectly outlined with silver . . . triangulifera 392 bulletin: museum of comparative zoology Body hardly exceeding hind wings even in male; triangular patch rounded, extending down only to 1st A, strongly edged with silver, especially the basal extension along costa scaphoides Prolimacodes triangulifera Schaus P. triangulifera Schs., Jour. N. Y. Ent. Soc, 4, 56, 1896; Biol., 2, 444, 88: 12, 1898; Strand, Arch. Naturg., 1922A (7) 140 cf ; Hering & Hopp, D. E. Z. Iris, 41, 177, 3: 2 (d" genitalia). To be figured: Seitz, 167: d. All but one of our specimens show only scattered silver scales. Oct. 31-Jan. 11; May (see diagram). Ranges to Mexico, the closely related P. lilalia Dyar in Guiana. Prolimacodes scaphoides Hering P. scaphoides Hrg. & Hopp, D. E. Z. Iris, 41, 177, 3: 1 (