186 Psyche [October 
A GYNANDROMORPHOUS MUTILLID:! 
By Wituiam Morton WHEELER. 
On the first day of August, 1910, while I was collecting in a dry 
upland pasture near Colebrook, Litchfield County, Connecticut, 
my attention was attracted by a small Mutillid with wings only 
on one side. It was running over the ground very rapidly, and on 
being captured proved to be a very handsome lateral gynandro- 
morph of Pseudomethoca canadensis Blake, the right half of the 
body, including the appendages, being purely male and black, 
whereas the left half was largely of a rich red color and, except 
in a few insignificant details, purely female. Although the legs 
on the left side are stouter than those on the right the insect did 
not move in a circular but in a rectilinear path and was therefore 
able to compensate the difference in the strength of the appendages 
on the two sides of the body. The specimen was not dissected, 
since, owing to the small size of the abdomen and the hardness 
of the integument, I was sure of injuring the specimen and by 
no means sure of gaining an adequate conception of the structure 
of the reproductive organs. There can be little doubt, however, 
that these organs consist of an ovary on the left and a testis on the 
right side. The accompanying camera drawing of the insect in 
dorsal view, and of the head as seen from the front, together with 
the following description, will give an idea of the external structure: 
The specimen is a little over 5 mm. in length. The two halves 
of the body, owing to the pronounced sexual dimorphism, are 
asymmetrical. The head is much smaller on the right than on 
the left side. The eyes are of nearly equal size; two ocelli are 
present on the male side, namely the anterior, or median, and the 
right lateral ocellus. The right mandible is tridentate, the left 
simply faleate. The right antenna is 13-jointed and much longer 
than the left, which is 12-jointed. The sharp line which separates 
the black coloration of the right from the red of the left side of 
the head begins at the middle of the occipital border, runs forward 
just a little to the left of the median ocellus, and terminates 
a little to the right of the middle of the clypeus. The clypeus 
1€ontributions from the Entomological Laboratory of the Bussey Institution, Harvard 
University. No. 27. 
