SILPIIIDAE. "77 



The imperfectly developed eyes of the latter genus are situated 

 in the same position iu relation to the hind augies of the head as 

 in Adelops.- 



Leptinus is represented by L. ledaceus Mull., common to 

 Europe and America, living with various small rodents and in- 

 sectiyora, either on their bodies or in the material of their nests, 

 but whether as true [)arasites or merely as guests has not been 

 determined. 



Leptinillus validus (Horn), much larger than the former, is 

 from the Hudson Bay region. Of its habits nothing is known. 



Fam. X.— silphidae. 



Mentum quadrate, sometimes slightly emarginate, fre- 

 quently with a transverse piece between it and the ligula, 

 wliich is prominent, emarginate, or bilobed; gular suture 

 distinct. 



Maxillao with two lobes, innei' one sometimes with a 

 terminal hook. 



Eyes finely granulated, sometimes absent. 



AntenUcTS inserted under the margin of tln^ front, behind 

 the base of the mandibles; 11-jointed, rarely 9- or 10-jointed : 

 gradually or suddenly clubbed at the apex, sometimes nearly 

 filiform. 



Prothorax with the epimera and episterna not distinct. 



Mesosternuni very short, side pieces attaining the coxae. 



Metasternum large, nearly truncate behind; episterna 

 long; epimera large, distinct. 



Anterior coxse large, conical, contiguous; middle coxa; 

 oblique, not prominent; posterior contiguous (except i*n 

 Lyrosoma and all eyeless genera), not extending to the 

 margin of the body, prominent internally, rarely (Clambini) 

 laminate. 



Abdomen with six free ventral .segments, except in Sphje- 

 rites, which has but five. 



Legs sometimes thick, subfossorial (Nccroyjhorus), some- 

 times very slender (Pteroloma); tibiae with large terminal 

 spurs, the anterior ones of the male usually dilated; poste- 

 rior trochanters prominent, or not; tarsi usually r)-Jointed. 



This family contains species whicli live on decomposing animal 

 matter or on fungi; some species of Catops are found only in 



