SOME NEGLECTED SET OF LEPIDOPTEROUS LARVA. 
By HARRISON GARMAN. 
A study of the corn-ear worm larva with reference to its 
external structure* has revealed series of microscopic sete, 
some of which appear to have been overlooked by other writers 
when dealing with the Noctuide and are thus not recognized 
in the systems employed, though they are as constant in every 
way as the larger sete to which numbers, or Greek letters, 
have been assigned. As opportunity arose the author has 
examined larve of other families of moths and finds the same 
sete present, though showing some variations with family, 
in their numbers, in position on the body, and in their relation 
to each other and to certain of the large seta. As examples 
of these variations I am presenting figures made from greatly 
enlarged photographs of the skins of one of the Cosside, 
Prionoxystus robinie, the well known Carpenter worm of black 
locust trees, and of Tholeria reversalis, one of the Pyralide. 
The body of the carpenter worm when about half grown bears round 
brownish tubercles upon which the sete arise, the pigment of the 
tubercles serving as a guide in locating the sete and enabling one to 
find with no special difficulty even the smallest of them. This larva 
bears six large setee on each side of its neck plate, and one microscopic 
seta at the posterior edge of each half, the latter being the homolog of 
the one noted on the neck plate of Chloridea. The neck plate bears 
also on each side three sense pores, the lateral one minute, and a gland 
outlet outside and a trifle posterior to seta ma. A ventral microscopic 
seta 1s present on the prothorax anterior to the base of the jointed leg, 
and a second just in front of the base. 
The mesothorax and metathorax are alike in the number and 
arrangement of sete. A single microscopic seta is present at the 
anterior edge nearly in line with seta mb of the neck plate. Exterior 
to these setze, in line with the ventral sense pore of the neck plate, is on 
both meso- and metathorax a pair of microscopic setz; otherwise the 
microscopic sete are like those of the prothorax. The fourth body 
somite (lst abdominal) bears a seta at its anterior edge, in line with the 
one on the thoracic somites, but lacks the lateral pair of microsetz as 
does also the succeeding abdominal somites, but the microscopic seta 
Illa appears before the spiracle as an independent seta. The more 
* Bulletin No. 227, Kentucky Experiment Station. 
145 
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