1955 ] Severin — Melanoplus mexicanus mexicanus 107 
right half, however, is female with some distortion. A 
normal appearing upper and lower valve of an ovipositor 
are present on the right side. The right cercus is female 
in shape, while the left resembles the cercus of a male. 
The furculum on the left side is absent while on the right 
it is present and resembles in size and shape the furculum 
of the typical male. The supra-anal plate is bilaterally 
symmetrical and resembles rather closely the supra-anal 
plate of a male except for a transverse ridge extending 
across the right half of it. A subgenital plate is present 
but only the left half is developed. Consequently the ter- 
minal notch present in normal males is lacking in this 
gynandromorph. On the right side a terminal abdominal 
sternite resembling one-half of the end sternite of a fe- 
male abdomen is present. Even one-half of the so-called 
egg-guide terminates this sternite (see figures 1, 2, 3). 
