228 COLEOPTERA OF NORTH AMERICA. 



Anterior tibia? slightly dilated, with the outer angle very much prolonged; 



intercosal process of abdomen acute. Ammodoxus. 



Anterior tibiae very broad, triangular, outer angle slightly prolonged; inter- 



coxal process truncate. Ephalus. 



Tribe IV.-SCAURINI. 



Body elongate, apterous ; bead prolonged behind the eyes, 

 which are small, transverse, reniform, and coarsely granulated ; 

 front dilated at the sides and anteriorly ; labrum covered ; men- 

 turn small, with small inflexed lateral lobes ; ligula prominent ; 

 gular peduncle distinct ; palpi with the last joint dilated, trian- 

 gular ; antenna? 11-jointed, outer joints broader, rounded, sub- 

 transverse. Elytra not embracing widely the flanks of the ab- 

 domen ; epipleurae narrow, reaching the tip of the elytra ; meso- 

 sternum very short, side pieces narrow ; epimera distinct. Hind 

 margin of third and fourth ventral segments subcoriaceous ; third 

 aud fourth ventral sutures deeply impressed, the corresponding 

 segments scarcely emarginate in Eulabis and Apsena, deeply 

 emarginate in Cerenopus. Anterior coxae rounded ; middle 

 coxae with distinct trochantin ; hind coxae oval, very widely sepa- 

 rated ; legs moderate and simple (Eulabis), or long, variously 

 toothed (Cerenopus) ; tibial spurs distinct or large ; tarsi spinous 

 beneath. Scutellum broad, not penetrating between the elytra. 



But three genera represent this tribe in our fauna ; they differ 

 from all the neighboring tribes of the present sub-family by the 

 tarsi being clothed beneath with spines instead of hair. 



The genei'a may be distinguished as follows : — 



Head short, legs simple ; 



Mentum with a sudden elevation at the middle (body glabrous). 



Eulabis. 



Mentum nearly flat ; body slightly pubescent. Apsexa. • 



Head long ; legs of % toothed ; mentum nearly flat. Cekexopcts. 



The last genus inhabits Arizona, Texas, and the Colorado 

 Desert ; in the males the anterior tibiae are serrate internally, and 

 the hind femora are armed with several small teeth. The other 

 two genera are found in California ; Epantius Lee. does not 

 appear to be sufficiently distinct from Eulabis, but, on the other 

 hand, Eulabis pubescens Lee, the type of Apsena, while having 

 the form and sculpture of one of the species of Eulabis (E. ru- 

 fipes), has the mentum as in Cerenopus, that is, nearly flat, with 

 two impressions, separated by a faint medial elevation. 



