W. M. Wheeler.
Two Gynandromorphous Ants.
Psyche 26(1):1-9, 1919.

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PSYCHE
VOL. XXVI FEBRUARY, 1 9 1 9 No. 1
TWO GYNANDROMORPHOUS ANTS.l
Two gynandromorphous ants which have turned up in recent collections are of unusual interest since they differ significantly from any of the similar anomalies previously described. One is a gynandromorph in the strict sense of the term, i. e., a combina- tion of the female and male of our common La& (Acanthomyops) latipes Walsh, the other a dinergatandromorph, or combination of the soldier (dinergate) and male of a Philippine ant, Camponotw (Colobopsis) albocinctus Ahead.
For many years I have been expecting to find a gynandromor- phous Lasius, both because the species of this genus are among the commonest and most widely distributed Eurasian and North American ants and because it seemed to me that at least an erga- tandromorph, or combination of worker and male characters might occur as readily as in other ants, since these two phases in Lasius are of about the same size. On September 21,1917, while turning over a large stone at Colebrook, Conn., in a pasture less than a quarter of a mile from the spot in which I took the gynandromor- phous Mutillid described in a former number of PSYCHE? I found a compact cluster of about two hundred of the bright yellow work- ers of L. latipes and in their midst a black insect, which I took to be an unusually large male. I placed the specimens in a vial of strong alcohol and continued my collecting. On returning home I was surprised to find that the dark specimen was a remarkable gyn- andromorph of a Lasius in which the sexual differences are more extreme than in any other species of the genus or indeed of any of the North American ants, except the Ecitons. Many years ago McClendon and 13 endeavored to show that L. latipes is peculiar 1 Contributions from the Entomological Laboratory of the Bussey Institution, Harvard University, No. 153.
Z A Gynandromorphous Mutillid. PSYCHE 17, 1910, pp. 186-190, 1 fig. *Dimorphic Queens in an American Ant (Lasius latipes Walsh). Bid. Bull. 4, 1903, ppr
149-163, 3 figs.




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2 Psyche [February
in possessing two forms of females, one, which we called the (3- female, being reddish-yellow, with long golden pile, large, flattened femora and tibiae, short, slender tarsi and incrassated antennae; and one, which we called the a-female, of a darker color and inter- mediate in structure and pilosity between the @female and the female of L. claviger R0ger.l The gynandromorph taken at Colebrook is evidently a combination of the male and 6-female. These phases, when they appear as separate individuals measure respectively 4 and 8 mm., and could hardly be combined to form a viable lateral gynandromorph, so that it is probably for this reason that the specimen, as will appear from the description and figure, is of a different type. Unfortunately I did not have access to a dissecting microscope till the specimen had become so thoroughly hardened in the alcohol that I despaired of gaining any satisfac- tory knowledge of its internal reproductive organs. The gynan- dromorphous C. albocinctus was found among a small series of dried and mounted specimens collected for me in 1917 by Dr. F. X. Williams at Los Bafios, near Manila. The following detailed descriptions and the figures will give an idea of the external pe- culiarities of the two specimens.
Lasius (Acanthomyops) latipes Walsh (Fig. 1) Gynandromorph.
Length 8 mm., being that of the normal
fi-female, but with the thorax and gaster more slender. Head
shaped like that of a normal female, but with the eyes and ocelli much larger and more prominent, the right posterior ocellus smaller than the left and the surface black, with isolated, reddish-yellow spots as indicated by the less densely stippled areas in the figure. Left mandible of the female type, reddish-yellow , smooth, shining, sparsely punctate; right mandible black, like the left in form and size but subopaque and very finely longitudinally striolate as in the male. Clypeus with somewhat more than its right half red- dish-yellow (female), the remainder black (male). Antennae both alike, black, 13-jointed '(male) and with slightly swollen first funicular joint but stouter than in the male, in form only slightly approaching the female, as in normal individuals of this sex the scape is incrassated distally and the funiculus is spindle-shaped, with very broad and transverse joints in the middle. The surface 1 These females are figured in the paper cited and in my ant book (Fig. 55 B and C, p. 94).



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of the head is subopaque as in the male and loot smooth and shm- ing as in the female, but the piloaity is long as in the latter though the haira are dark and not golden, as in the female. Thorax similar to that of the female but the pro- and epinotum are some- what narrower and the former is asymmetrical, being shorter on the left than on the right side so that the head is turned to the left. The mesonoturn and seutellum are more like those of the male. The thorax is black and has the same sculpture and short, sparse piloaity as in the male, with the exception of the epinatuzn, which is reddish-yellow and has the long, abundant, golden hairs of the female. The petiole, too, is entirely of the female type in shape, color and pilosity. The gaster is narrower and more pointed posteriorly than in the normal female and with six visible segments and therefore more nearly of the male type. Its first and second segments are entirely black above (male), the third reddish-yellow (female), except for a black, asymmetrical transverse blotch at the



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anterior border on the dorsal surface; the fourth, fifth, and sixth segments are black (male), but the fourth has an irregular reddish- yellow band extending over its full length on the right side above, and the fifth has a small spot of the same color on the same side at the anterior margin. On the ventral side the first segment is, black throughout, the second with an oblique reddish-yellow blotch to the left of the median line, the third with a narrow black longi- tudinal streak in the middle and a large rounded black spot on the left posterior corner. The fourth ventral segment is entirely black and very small, the fifth yellow. External genitalia of the male type, much as in normal individuals but more robust and turned somewhat to the right side.
Sculpture, pilosity and pubes-
cence of the gaster as in the male. Legs very peculiar in that the hind pair, including their corn, are of the normal female form, pilosity and color, whereas the right fore leg and left middle leg, including their coxse, are entirely black and in form intermediate between the male and female types though somewhat more like the latter in form and size. Left fore leg black on its extensor and reddish yellow on its flexor surface and more nearly like the nor- mal female fore leg in form than the right fore legi Right middle
leg much more like that of the female than the left middle leg, the cox* and femur black, the latter with a long fusiform reddish- yellow spot on its extensor surface, the tibia and tarsus reddish- yellow throughout as in the female. The piloshy on the legs is short and sparse (male), except along the flexor border of the left fore tibise and on the hind legs where the hairs are long and of the female type. Both pairs of wings are normally developed and in size and shape as in the female, but the bind pair dropped off read- ily soon after the specimen was placed in alcohol, whereas the fore pair remain firmly attached, showing a pronounced tendency to deaJation (female) only in the metathoracic articulations. The
fore pair has the posterior half of the recurrent vein absent. This reveals a condition half way between those of the normal female and male, since in the former the recurrent vein is complete and closes the discoidal cell, whereas in the male it is usually entirely absent so that the wing is without a discoidal cell. The unusual interest of the specimen lies in the fact that it can- not be placed in any of the categories of gyliandromorphs, for as a whole it belongs neither to 'the more frequent lateral, nor to the



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19191 WheelerÌÔTw Gynandromorphous Ants 5 rarer anteroposterior, decussating, mosaic or blended types, but exhibits a mixture of all of them. The mandibles and clypeus have the sexual characters of the lateral type but the arrangement of colors in the clypeus is the reverse of that of the mandibles and hence decussating. The head is female in form but partly blended, partly mosaic and feebly lateral. The eyes, antennae, anterior ocellus and left posterior ocellus are strongly male. The right posterior ocellus, the right eye, which is distinctly smaller than the left, and the large area of reddish-yellow integument sur- rounding it, show that the right side of the head is more female than the left. The thorax in front of the epinotum is a blend of male and female characters, the pronotum being more female, the mesonotum and scutellum more male as are also the color, sculp- ture and pilosity of these three regions, whereas the epinotum and petiole are purely female. The wings are female but with the female tendency to dealation only in the hind pair and the reverse or male tendency to persistence in the articulations of the anterior pair. But the latter show in the retention of the anterior half of the recurrent vein a very interesting condition precisely half-way between that of the normal male and female wing. The hind legs are purely female but the two anterior pairs show a peculiar decus- sation, the left fore and right middle leg being more female in form and coloration and the right fore and left middle leg more male. This decussation of characters is similar to that of the mandibles and clypeus but less pronounced. It is very probable that the internal reproductive organs are more or less hermaphroditic, as they are situated in segments which externally exhibit a very striking mosaic of male and female characters. Camponotus (Colobopsis) albocinctus Ashmead (Fig. 2c) Dinergatandromorph. Length 4 mm.
In all respects like a normal soldier, except in its smaller size (the normal soldier measures about 5 mm.) and in having the head asymmetrical, with its smaller right half exhibiting male charac- ters. The right eye is larger, more convex and nearer the middle of the side of the head than the left. The right antenna is 13- jointed, with the terminal joint short and aborted, and the right mandible, though much shorter than in the male (Fig. 2a) has only two teeth separated by a wide concavity of the apical border..



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6 Psyche [February
The clypeus on the right side has the lateral extension characteris- tic of the male and the same type of frontal carina, whereas the left frontal carina is prolonged backward as in the soldier (Fig. 21') but does not border so deep a scrobe-like depression. In the
soldier the head is ferruginous or yellowish-red, with its posterior third infuscated, but in the male entirely black. In the diner- gatandromorph the infuscation extends much further forward between the frontal carinse and onto the right side. There are no Fig. 2. Camponotus (Colobopsis) albocinctus Ashmead. a, head of male; b, of
soldier; c, of dinergandromorph.
traces of ocelli. As the thorax, petiole, gaster and legs are in all respects like the corresponding parts of a normal though small soldier the internal reproductive organs are, in all probability, those of a normal soldier, i. e. of the abortive female type. I have not seen the worker of C. albocinctus but there can be no doubt that as in other species of the subgenus it has a small head, more rounded, less rectangular and narrower in front than in the soldier, with less convex mandibles and the clypeus shaped more as in the male. The species of Colobopsis are peculiar in having sharply marked soldier and worker forms, whereas in other sub-



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19191 WheelerÌÔT (tunamhmwrplwus Ants ' 7 genera of Cam- the workers are polymorphic, i. e. form a more or less evenly graded series from maximal to minimal in* dividuals. To my knowledge this is among ants the only known gynandmmorph that exhibits an unmistakable combination of male and soldier characters. In other cases the male charactera are combined either with the worker or with the female. Even
the lateral gynandromorph of CampOJWtUS ligniperda, described and figured by KlapSIekL represented a combination of the male and worker minor.
The dinergatandromorph of C. albocZnetus seems to me to be very significant in connection with the previously known thirty Fonnicid gynandromorpha and the Lasius Wipes described above? It is evident that the male characters may be combined not only with the female as in the gynandromorphs of other animals, but also with the soldier and worker. And although the latter are abortive females, they nevertheless behave in combination with the male like entities quite as distinct and independent as the fertile female. This suggests that the worker and soldier are not products of nutrition but are germinally predetermined. In other words, it would seem that in ants with male, female and worker castes, we must postulate three, in species with a soldier caste, four different kinds of eggs. This view is also supported by the following considerations: first, Bugnion and Miss Thompson have shown that in termites, which have developed castes surprising1 y like those of ants, the soldiers, workers and sexual forms can be recognized as distinct on hatching from the egg; second, embryo- logical study has shown that the insect egg is the most precociously specialized of all animal ova, so specialized, h fact, that not only the anterior and posterior poles but also the dorsal and ventral and right and left sides of the organism that is to arise from it are mor- phologically predetermined even before the extrusion of the polar bodies; and third, artificial castration has shown that operations on the primary sexual characters of young insect lam fail to dii- turb the development of the secondary sexual characters and instincts.
1 Ob&tnik Cnmpouotun lignipeitiw Lab. Sitzb. Bitem. Qes. WIBB., 1898,4 M., 3 fige.; Wheeler,Some New GylKndrornorphua Anta, with & Review of the Previously Recorded Casee. Bull. her. MUB. Wat. Hist, 19, 1913, p, 675, Kg. 11. a Reviews of the known case9 are rives in my papers: Some New Gyutliidromorphous Ants. eta., toco citslsi, pp. 653483.11 fi*. and Gynand~ottiorpbous Anta Docribed du* the Denada 1003-1913. her. Natural, 48, 1914, pp. 49-53.



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8 . Pwche (February
All these considerations point to the conclusion that in such veiy ancient and extremely specialized organisms as inserts, sex and caste peculiarities have been impressed oh the organization of the very young egg and are not determined by fertilization or by the incidence of trophic stimuli during larval development. I was, therefore, led in my first paper on the ant gynandromorph to postulate its origin from a pair of fused oScytes. The difference
between the various types of gynandromorplisÌÔlatera1 frontal, mosaic, blended, etc.-was supposed to be due to the differences in the two lands of ova, the plane of their fusion, regulatory ten- dencies that would avoid reduplication of organs, and differences in growth in the component ova or their parts to account for such cases of imperfect lateral gynandromorphs, as e, g. that of the Campmofw albocinctus described above, in which the male is so much smaller than the soldier component. My views have been treated as dnkl y heretical by Boveril and his pupil, FrSuleia Elsa Mehling: but Cockape: who has recently made a comprehensive study of Lepidopteran gynandromorphs, while pointing to certain defects in,my hypothesis, remarks that "it explains better than any other how in hetemchroic ffynandromorphs the areas occupied by the two colors and two sexes are identical. "He also mentions with approval the fact that "Doncaster has recently suggested that a gynandmmorph is produced by the fertilization of each of the nuclei of a binucleate ovum by a separate spermatozoon. He has proved the existence of these binucleate ova and has actu- ally proved the conjugation of a separate spermatozoon with each and seen the resultant mitoses." I should, of course, regard such a binucleate ovum as the first result of the fusion of two ova. The hypothesis of Boveri and Fraulein Mehling, according to which the gynandmmorph arises from an egg in which one of the two first cleavage nuclei unites with a sperm, is disproved, ac- cording to Cockayne "by the existence [in certain Lepodoptera] of perfect halved gynandromorphous hybrids both sides of which ahow equal admixture of the characters of both parents." Mor- gan has more recently endeavored to m o d for gynandromorpha 1 Uebet die Entetehung der Eugateraahea Zwitteibienan Aroh. Entwiold. Meth. Onr. 41, 1918, pp, 2M-311,2 pb.
tTJeber die Gynandromor&en Bienen dea Eugsteraohen Stockem. VerhandL phyis. ined. Oes. Warzburg 43. 1915, pp. Ha-228, S pts. *"Gylumdromoitp'hram" and Kindred Problm, Joan. Genet. 5, 1916, pp. 76-129.5 ptÌö




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19191 MetcalfÌÔ Malformed L eptinotarsa d ecemlineata 9 in Drosophila as due to a lagging sex-chromosome. As a full ac- count of his researches has not yet been published, I am unable to undertake the task of harmonizing it with what I conceive to be the conditions in the Formicidse.
A MALFORMED LEPflNOTARSA DECEMLINEATA.
BY C. L. METCALF,
Ohio State University.
The two accompanying illustrations show an interesting and peculiar malformation of a specimen of the Colorado potato beetle. The specimen was col-
lected by Mrs. Cleo F.Metcalf
at Orono, Maine, August 17,
1916. It was taken in com-
pany with many normal indi-
viduals feeding upon potato.
Unfortunately its peculiar con-
dition was not noted until it
had been killed. A prolonged
search failed to reveal any
other specimens in any way
abnormal. The chief purpose
in describing it here is to
record for the curious natural-
ist, who does not lack a sense
of humor, a freakish, though
not uncomely, product of one
of nature's sportive moods.
The visible abnormality con-
sists of a deep, V-shaped ex-
cision of each elytron extend-
ing from the apex to about
the basal third of the normal
elytron. The elytra are a little
Fie. 1. Malformed Levtinotarsa decem-
foreshortened ; the rniddorsal lineafa, showing anomaly in structure and pattern of the elytra; below, same in lateral line is nearly straight in side view.
About three times natural size.
view; and the usual convexity
covering the tip of the abdomen is entirely wanting, leaving the abdomen exposed from behind.




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