48 
Psyche 
[March 
A GYNERGATE OF MYRMECIA 
By George S. Tulloch 1 
Although gynandromorphs of male and female-includ- 
ing winged female, soldier and worker ants — have been 
noted from time to time, there has been no case recorded 
of a form exhibiting a gynandromorph-like combination of 
female and worker characteristics. The absence of such 
a form has supported the trophic 2 rather than the germ- 
inal, or blastogenic hypothesis of caste determination. 
Such an anomaly, here designated as a gynergate, was re- 
cently discovered in Dr. W. M. Wheeler’s collection and 
with his kind permission is described below. The specimen 
is a large Ponerine, Myrmecia ( Promyrmecia) aherrans 
Forel, taken in Wagoa, New South Wales by W. W. Frog- 
gatt in 1904. The right half of the insect has character- 
istics of a female 3 while the left half has those of a worker. 
In the head (fig. 1) the structure of the opposite sides 
appears to be quite typical of their respective castes, but 
the lateral margin of the right (female) side is distinctly 
concave and the posterior corner angular while the left 
(worker) side is convex and the posterior corner broadly 
rounded. The right eye is slightly larger than the left, and 
the clypeus is prolonged further forward on the right side 
than on the left. 
Structural characteristics peculiar to the component 
forms are prominent in the thoracic region. The structure 
of the right (female) side (fig. 2) indicates that this speci- 
men once bore two vestigial wings. The anterior one has 
been broken off (its position indicated by an insertion, W) 
1 Contribution from the Entomological Laboratory of Harvard Uni- 
versity. 
2 Santschi (1920) Bull. Soc. Vaud. Sci. Nat., Vol. 53, p. 177. 
3 The winged forms of the subgenus Promyrmecia are unknown; 
hence, the comparison of the female structures have been made with 
those of related species of the subgenera Myrmecia and Pristomyr- 
mecia. 
