TENEBRIONIDAE. 229 



Tribe V.— TENEBRIOIVIIVI. 



Body moderately elongated, apterous, or winged ; head pro- 

 longed, but scarcely narrowed behind, not received in the thorax 

 as far as the eyes, which are transverse and emarginate, mode- 

 rately finely granulated ; front dilated on the sides, covering the 

 base of the mandibles ; epistoma truncate or slightly emarginate, 

 not separated from the labrum by aclypeus ; antenna? 11-jointed, 

 gradually thickened externally ; mentum small, partly concealing 

 the ligula, inserted upon a gular peduncle ; elytra embracing 

 feebly the flanks of the abdomen ; epipleurae narrow. Anterior 

 coxae globose ; middle coxse with distinct trochantin ; legs long ; 

 tibial spurs small ; tarsi clothed beneath with silky, golden pu- 

 bescence, or with ordinary coarse pubescence. Hind margin of 

 third and fourth ventral segments subcoriaceous. 



This tribe embraces the Coelometopides of Lacordaire, with a 

 portion of his Tenebrionides ; the vestiture of the tarsi appears 

 to me to be of more structural importance than the length of the 

 metasternum, by which merely apterous and winged species are 

 distinguished. The affinity pointed out between some of the 

 genera and the tribe Scaurini is very strong, and I am somewhat 

 in doubt whether Polypleurus would not be equally well placed 

 in the preceding tribe. 



The genera may be divided into three groups : — 

 Tarsi silky pubescent beneath ; 



Epipleurse not narrowed towards the apex of the elytra. Polypleuki. 



Epipleurae gradually narrowed towards the apex of the elytra. Upes. 

 Tarsi coarsely pubescent beneath. Tenebeiones. 



Group I.— Polypleuri. 



The genus Polypleurus, consisting of three species, found under 

 stones in the Atlantic States, is alone contained in this group. 



The hind coxae are widely distant, the legs slender ; the tarsi 

 are silky pubescent beneath ; the metasternum is very short, and 

 the epipleura? extend to the extreme tip of the elytra, and are not 

 narrower there than at the middle. The body is elongate ovate 

 in form, the thorax and elytra closely fitting together, the latter 

 with rows of distant fovea?, the alternate spaces being slightly 

 raised. The labrum and ligula are less prominent than in the 

 other genera of the tribe ; the mentum is subtrilobed, the middle 

 lobe wide, the lateral ones small and inflexed. 



