338 COLEOPTERA OF NORTH AMERICA. 



large ; the antennas are very long, the 6th joint is a little thickened 

 inwards at tip, and from the tubercle thus formed proceeds an 

 acute slender tuft of stiff hairs, resembling a spine. The 1st joint 

 of hind tars' pot elongated, scarcely equal to the 2d and 3d 

 united. 



Group II. — Liopi. 



This group is represented by many species in our fauna, all of 

 small or medium size, except one species from Arizona. 



The lateral tubercle varies in position from near the middle to 

 the base ; in the former position it is very obtuse, but as it moves 

 backwards it becomes more and more acute, and spiniform ; the 

 prothorax is feebly tuberculate in some species with obtuse late- 

 ral tubercle, and in the same species, the 1st joiut of the hizwl 

 tarsi is not elougated. 



The genera may be thus arranged : — 



Lateral tubercle submedial; outer joints of antennae shorter; 

 1st joint of hind tarsi not elongated ; mesosternum truncate ; 

 Body and limbs with long erect hairs ; lateral tubercle acute. 



Lophopojuai ? 

 Pubescent only, lateral tubercle obtuse. Leptostylus. 



Lateral tubercle of prothorax acute, post-medial; joints of antennae from 

 3d nearly equal ; 

 1st joint of hind tarsi as long as 2d and 3d united ; 



Lateral spine distant from base, body stouter; mesosternum truncate. 



Sternidius. 

 1st joint of hind tarsi very long ; mesosternum acute behind ; 

 Lateral spine distant from base, antennae not ciliate beneath. 



Liopus. 



Lateral spine basal or nearly so, antennae with a few ciliae beneath ; 



Body slender. Lepturges. 



Body stout, depressed. Hyperplatys. 



The new genus Sternidius is founded upon Amniscus varie- 

 gatus Hald. and allies, contained in division C of my revision, 

 Jouru. Acad. Nat. Sci. Phil., 2d ser. ii. 172 ; it differs from 

 Leptostylus only by the characters mentioned in the table. 



Group III. — Acanthocinl. 



The insects of this group are of medium, or above medium, size, 

 and elongate form; the lateral spine of the prothorax is well 

 developed (though shorter in Graphisurus), and is very little 

 behind the middle, except in Eutessus, where it is feeble, and near 



