278 



FAMILY VIII. — SILPHID^. 



been taken in Alaska, and near Washington, D. C, so that it prob- 

 ably occurs in Indiana. (Fig. 139, a.) Another, P. hamiltoni 

 Horn, occurs near Allegheny City. Pennsylvania. 



This tribe comprises insects of small size and usually ovate 

 form, having the front coxse eylindric-conic and contiguous, the 

 cavities closed behind; abdomen with six distinct segments, except 



Fig. 139. a, Pinodyks cryptophagcndes Mann.; (ti) antenna of same; b, Prionochoda opaca Say; (a) tibial spur 

 of same; c, Ptomopha^jus consobrinus Lee; (a) antenna of same. (After Eom.) 



Tribe III. CHOLEVINI. 



in Colon, and covered by the elytra. Some of the species live on 

 carrion or in fungi ; others in ants ' nests. Four of the eight genera 

 are represented in Indiana. 



KEY TO INDIANA GENERA OF CHOLEVINI. 



a. Abdomen with six segDieiits ; hiud coxae contiguous ; head suddenly nar- 

 rowed beliind the eyes, forming a necli, the occiput elevated in a 

 ridge. 

 6. Elytra punctate, not strigose; last joint of maxillary palpi as long as 

 the preceding; mesosternum not carinate, the middle coxte con- 

 tiguous, 

 c. Tibial spurs moderate in length, simple. IV. CnoLEVi. 



cc. Tibial spurs very long, bipectinate. (Fig. 139, 6.) 



V. Prionochjeta. 

 66. Elytra finely and transversely strigose; last joint of maxillary palpi 

 short, awl-shaped ; mesosternum carinate, the middle coxoe sepa- 

 rated ; antennae gradually clavate, not longer than head and thorax. 

 (Fig. 139, c.) VI. Ptomophaqus. 



00. Abdomen with five segments (often four in female) ; head oval, not nar- 

 rowed behind, occiput not elevated ; hind coxae contiguous. 



VII. Colon. 



IV. Choleva Latr. 1796. (Gr., "to Hmp or halt.") 



Small, usually oval species, narrowed behind and having the sur- 

 face finely pubescent and the elytra usually finely punctured. The 



