28 



Bulletin No. 159 



is small, firm-walled, with a few setse arising from its 

 dorsal surface; on each side with two black specks a short 

 distance behind the base of the antenna, the dorsal of which 

 is larger. Head 0.286 mm. long, being a little more than 



Fig. 10.— Mouth-parts of iBrva of Tanytarsus sp. r?, labium; /'.mandibles: 

 <■. labrum witii characteristic spines; d, left antenna. 



twice as long as the antennae. Prominences on which an- 

 tennas arise, evident. Antenna, .01358 mm. long; 1st seg- 

 ment slightly curved, a little more than three times as long 

 as the second, bearing at its tip a slender appendage some- 

 what longer than the second; second segment straight, 

 slightly enlarging from base to tip, bearing at its extremity 

 two acute appendages about two-thirds the length of the 

 remaining joints; third, fourth, and fifth segments minute 

 and tapering. Labrum with two strong pectinate claws 

 curving toward the ventral side; on each side of these claws 



■^■fy. 



Fig. II.— Larva of Tanytarsus removed from case, x 23. 



are about five smaller simple claws of the same general 

 character, all being evidently of service as grappling hooks. 

 Mandibles strong, curved, with black teeth, as follows : an 

 apical rather short tooth, a very long strong tooth just 

 within it, then three shorter teeth of about equal size; 

 within the latter the mandible expands, as in other related 

 genera. Labium with black teeth, the median largest and 



