'I'lii: i.AMKi.i.icoKX i)i:i:Ti,K^;. ;)41 



were iVoiii llic li;ilt'-ilric(l cjircjiss ol" ;i do^-. 11 seems, thcfcroi'c, 

 lli.il this species soiiicl iiiics li;is tlii' li;iliils of Trox, a gciuis willl 

 wiiii'li i1 is cldscly jillicd jiiid in wliicli it, was placed by Say. 



Tribe \ 1. TKOCIXI. 



Ohlonp:, convex, dii'ty-lookiii;; lu-ciwii beetles, wliicli occur under 

 or about tbe skins and l)ones ol' carrion, old hides or featliers. M'he 

 sui'face is usually rougbly scul|)tured and eovei'iul with a ci'ust ot* 

 eartb whieli is dil'lieult to remove. Krom tbe prei^eding' tribe tbey 

 differ in form and by bavino- tbe side pieces of mesothorax not 

 reaching tbe ronnded middle coxa\ Tbey possess a distinct stridn- 

 lating organ in tbe form of an (>lliptieal plate witb pearly retlee- 

 tions, located on tbe upper ]iart of tbe outer face of tbe first ventral 

 segment, and covered b\- tbe elytra. A small oval polished space 

 on tbe inner surface of tbe elytra near tbe margin and about op- 

 posite tbe ]date serves as an aid in producing tbe sound. All of 

 our species belong to tbe single genus Trox. Tbe following are tbe 

 principal papers treating of the North American forms : 



LcConte. — "Descriptions of the species of Trox and Omorgus in- 

 habiting the Ignited States," i)) Proc. Phil. Acad. Nat. Sci., 

 VII, 1854, 211-216. 



Horn. — "Revision of tbe Species of Trox of the United States," 

 in Trans. Anun*. Entom. Soc, V, 1874, 1-12. 



XVII. Trox Fab. 1702. (Gr., "a gnawer.") 



Twenty-one species of this genus are recognized from tbe United 

 States, 14 of which have been taken in Indiana, while one other 

 jierhaps occurs. Sometimes a half dozen or more species are found 

 in company in or beneath the same old skin or other remains of 

 carrion. T^nless cleaned of their usual encrusted coat of dirt, tbe 

 specimens are very difficult to classify. 



KEY TO TIIK IND1A.\A SPECIES OF TROX. . 



0. Scutellum spear-shiipe<l, i. e., narrowed strongly near the base, its sides 

 at middle aiigulatc: larger species. 12 or more mm. 

 J). Klytra with rows of lul)ercl('s very distinct and 1(.iiientose. or cov- 

 in-e<l with fine hairs, 

 c. First .joint of antcnn;e with dark lirown liairs; cinh darl^. 



1777. scABKosrs. 

 c<: First .joint ol' anlcnn.-i' witii reddisli-lirown haii's: clnli riMldish- 

 brown or asli-yray. 

 (1. Elytrnl tubercles nmnd. llieir entire surface tomentose. 



177S. MONAcins. 



