154 COLEOPTERA OF NORTH AMERICA. 



Third joint of tarsi much prolonged at the side ; hind tarsi with the first 

 and second joints equal ; scutellum small. Actenodes. 



Tribe II.— THRI1VCOPYGINI. 



This tribe contains but a single genus, Thrincopyge Lee, with 

 two species from New Mexico ; the general form is elongate and 

 depressed. 



The front is not contracted by the insertion of the antenna? ; 

 the mandibles are short, thick, and obtuse ; the mentum is en- 

 tirely corneous ; the antennal pores are situated in small marginal 

 fovea?. The scutellum- is distinct. The prosternum is broad, with 

 the sutures oblique ; the sides are not angulated behind the coxa?, 

 and the tip is obtusely rounded, fitting into the emarginate meso- 

 sternum ; the mesosternal suture is distinct. The hind coxae are 

 just as in the preceding tribe, dilated inwards, with the anterior 

 margin straight, the posterior oblique ; the epimera of the rneta- 

 thorax are triangular, not covered at all by the abdomen. The 

 last ventral segment has a deep groove running around the sides 

 and tip. The tarsi are broad ; the ungues simple and distant. 



Tribe III.— JITLODIIVI. 



The species of this tribe are convex, and of a conical form, 

 narrowed behind, rarely cylindrical or very elongated ; nearly all 

 are clothed with erect hair. The front is not contracted by the 

 insertion of the antenna? ; the mentum is entirely corneous ; the 

 antennal pores are diffused in the foreign genus Julodis, but con- 

 tained in marginal foveas in our genera. The thorax is truncate 

 at base, and closely applied to the elytra. The prosternum is 

 broad, with the sutures oblique ; the sides are not angulated be- 

 hind the coxa?, and the tip is obtusely rounded. The mesosternum 

 is deeply emarginate, rarely divided ; the mesosternal suture some- 

 times distinct, sometimes obsolete. The hind coxa? are narrow, 

 not dilated internally ; the anterior margin is straight or slightly 

 concave, the hind one scarcely oblique ; externally they are slightly 

 wider than at the middle, and the usual prolongation of the abdo- 

 men, which limits them, is covered by the elytra. The epimera 

 of the metathorax are triangular and small, but not covered by 

 the abdomen. The first joint of the hiud tarsi is elongated in 

 our genera ; the claws are either simple or toothed. 



