1928 ] 
The Larva of Leptanilia 
85 
THE LARVA OF LEPTANILLA (HYM.: FORMICID^) 1 
By George C. Wheeler, 
University of North Dakota 
Leptanilia revelierei sardoa Emery 
Larva : Body long, slender ,subcylindrical, or thocephalic and 
straight except for the thorax which is slightly curved ventrally; 
with eleven distinct postcephalic segments. Diameter greatest 
at the sixth abdominal segment; decreasing slightly toward the 
posterior end which is rounded and terminates in a small hemis- 
spherical boss; and diminishing progressively to the anterior 
end, except for a slight constriction at the first abdominal seg- 
ment. Relative diameters of the segments (beginning with the 
prothorax as the unit) : 1 . 00-1 . 30-1 . 50-1 . 45-1 . 80-2 . 00-2 . 45- 
2 . 80-3 . 00-2 . 95-2 .75. Relative lengths of segments : 1.0-1.9- 
3.4-3. 1-3. 6-4. 0-5. 3-4. 0-3. 7-3. 3-7. 7. (Fig. 1 A) 
Projecting downward and forward from the ventral side of 
the prothorax there is a curious structure suggestive of a plow- 
share. This is furnished with three hairs: a short, simple, 
slightly curved seta arising just back of the apex on the ventral 
side, and two longer pendulous hairs, which are curved at their 
distal ends and bifid at the tips, arising dorsolaterally just back 
of the middle of the structure. (Fig. IB and E ) 
On either side of the fourth abdominal segment near the 
posterior border there is a bare circular area enclosed by a 
narrow heavily chitinized band, the whole structure (provisional- 
ly called “tympanum”) being about 0.037 mm. in diameter. It 
is bordered by a fringe of stiff hairs, which are stouter and a 
trifle longer than those on the adjacent integument; there are 
also a few of these on the heavily chitinized band. Attached to 
the bare area near its posterior margin is an internal tube-like 
structure; this is twice bent and its diameter increases toward 
the inner end; its length is about 0.06 mm. (Fig. ID) 
Contribution from the Zoological Laboratory of the College of Liberal 
Arts at Syracuse University. 
