104 COLEOPTERA OF NORTH AMERICA. 



The genera are numerous, and cannot be recognized without 

 close observation ; the following table will, we hope, be sufficient 

 for ordinary studies : — 



Maxillary palpi with the last joint not subulate. 2. 



Maxillary palpi with the last joint smaller and narrower, subulate. Iti. 



2. Hind tarsi with joints 1-4 unequal. 3. 

 Hind tarsi with joints 1-4 very short, equal. 14. 



3. Hind tarsi with the 1st joint elongated. 4. 

 Hind tarsi with joints 1-2 equally elongated. 9. 



4. Maxillary jjalpi with 4th joint longer than the 3d. 5. 

 Maxillary palpi with 4th joint conical, equal to the 3d. Porrhodites. 

 Maxillary palpi with 4th joint broader, pyriform. Geodroruicus. 



5. Maxillary palpi wide, short, 4th joint stout ; tibiae spinous. ti. 

 Maxillary palpi long, slender, 4th joint less than twice as long as 3d. 



Tilea. 

 Maxillary palpi with 4th joint four times longer than 3d. Lesteva. 



6. Antennae subfiliform, gradually slightly thickened. 7. 

 Antennae with joints 5-11 suddenly thicker. 8. 



7. Hind tarsi with 1st joint only elongated. 



Mandibles short, mutic. Acidota. 



Mandibles short, the right dentate at middle. Arpedium. 



Hind tarsi with 1st joint very long, 2d elongated, but shorter. 



Amphichroum. 



8. Front prolonged into a beak as long as the head. Tanyrhinus. 

 Front but slightly prolonged. Trigone demus. 



9. Front coxae large, conical, prominent. 10. 

 Front coxae small, transverse, not prominent. 12. 



10. Antennae slender. 11- 

 Antennae thickened externally, tibije spinous. Lathrimaeum. 



11. Tibiae spinous. iOeliphrum. 

 Tibic-B pubescent. Olophrum. 



12. Hind tarsi with 5tb joint equal to the others united. Pycnoglypta. 

 Hind tarsi with 5th joint longer than the others united. Acrulia. 



14. Elytra long. 15. 

 Elytra very short. Micralymma. 



15. Tibiae finely si)inous. Homalium. 

 Tibia; pubescent. Anthobium. 



l(j. Maxillary palpi with 4th joint longer, slender. 17. 



Maxillary palpi with last joint very small. 18. 



17. Hind tarsi with 1st joint twice as long as 2d. Orobanus. 

 Hind tarsi very short, 1st joint not longer than 2d. Microedus. 



18. Maxillary palpi with 3d joint long, obconical ; antennae slightly and 



gradually thickened ; hind tarsi with 1st joint a little longer than 



the 2d. Ephelis. 



Maxillary palpi with 3d joint thick, oval ; antennae shorter and mucli 



stouter ; hind tarsi with joints 1-4 nearly equal. Eudectus. 



