FIELD BOOK OF INSECTS. 



4. Labrum present; palpi well developed, flexible; form 

 elongate-oval. Feed on the staminate flowers of conifers. 



Rhinomacerinas. 



Labrum absent; palpi short, rigid 5 



5. Mandibles flat, toothed on inner and outer sides; 

 tibia? with short terminal spurs at tip; claws free, bifid 

 or acutely toothed; form usually elongate-oval, somewhat 

 depressed. Rhynchitinae. Rhynclrites bicolor (elytra, pro- 

 notum and head, back of eyes, red, otherwise black; length 

 .25 in.) breeds in the "hips" of roses. 



Mandibles stout, pincer-shaped; tibiae armed at tip 

 with two strong hooks; claws united at base; form short- 

 oval, robust Attelabinas (p. 398). 



6. Tip of abdomen covered by elytra; trochanters large, 

 femora attached to their apex; form pear-shaped; not over 

 .2 in. long. Apioninas. There are many species of Apion, 

 one of which is abundant in late summer on Wild Indigo. 

 Podapion gallicola makes rather spherical galls on pine 

 twigs, and is rare. 



Tip of abdomen exposed ; trochanters small 7. 



7. First joint of antennas longer than the second 8. 



First joint of antennas no longer than the second; 



beak short, broad; hind coxae very widely separated; legs 

 elongate, clasping; length less than .13 in. Tachygoninre, 

 the only genus being Tachygonus. 



8. Kind femora very broad, their outer margin strongly 

 curved, wrinkled; beak very slender, cylindrical; length 

 about .14 in. Allocorhyninae, Allocorhynus slossoni from 

 Florida being the only known eastern species. 



Hind femora normal; beak short and broad; length .5 

 in. or more. Ithycerinas, the large Ithycerus noveboracensis 

 being the only known eastern species. 



9. Antennal club usually ringed, not shining; tarsi usually 

 dilated, third joint bilobed, brush-like beneath, though 

 narrow and setose in some more or less aquatic species; 

 abdomen of male with an extra anal segment 10. 



Antennal club with its basal joint usually enlarged or 

 shining or both, feebly or not at all ringed ; tarsi frequently 

 narrow, not brush-like beneath 12. 



10. Prosternum simple, or grooved to receive the beak, 

 not forming a triangular plate in front of the coxas 1 1 . 



396 



