THE CANADIAN ENTOMOLOGIST. 207 



Trox, Fabr. 

 The species of Trox are rough, dirty-looking, brown insects, usually 

 more or less incrusted with earthy matter, found under dry carrion and 

 old hides or feathers. I'hey are quite uniform in appearance and are 

 consequently not readily separated, more particularly as they vary to 

 some degree in sculpture within specific limits. I am entirely unable to 

 find constant and easily recognized characters on which to make groups 

 otherwise than those established by Dr. Horn, and the table, therefore, 

 follows his own exactly : 

 A. Scutellum hastate (/.<?., shaped like a spear-head). Large species. 

 Sides of prothorax near base often with feeble incision. Elytra 

 with rows of distinct smooth tubercles. Length, 



.48 to .66 in piindatus, Germ. 



AA. Scutellum oval, species smaller. Hind femora without spinules on 

 posterior margin. 



b. Tubercles of elytra with black setae. 



Tubercles elevated, setae erect, rather long. Length, .25 to 



.28 in er'maceus. Lee. 



Tubercles indistinct, setae short. Length, .36 



to .44 in capillar is. Say. 



bb. Tubercles of elytra with pale or rufous hairs or scales. 

 c. Elytra distinctly tuberculate. 



d. Thoracic ridges straight or nearly so. 



Elytral margin serrulate or crenulate at base. Length, 



.2410 .32 in.. sordidtis, l^ec. 



Elytral margin entire at base. Lengtl\, .40 to 



.48 in unistriatus, Beauv. 



dd. Thoracic ridges very sinuous. Length, .20 to 



. 24 in terrestris, Say. 



cc, Elytral tubercles very indistinct, being replaced by patches 

 of setae. 

 Anterior tibiae not serrulate above the lateral tooth. 



Length, .25 in cequalis, Say. 



Anterior tibice serrulate near the base. Length, .20 to 

 .28 in scaber, L 



