AMERICAN COMPONENTS OF THE TENTYRIINyE 365 



elytra become rugose, an accidental variation often seen in 

 Cojn'o)iiis and some other Tenebrionids. 



Tribe Auciimobiini. 



This is the only tribe, the propriety or legitimacy of which is 

 at all doubtful to me. The single species, Auchmobius siib- 

 IcBvis^ was described many years ago by LeConte (Ann. Lye. 

 N. Y., 185 1), in few words and has been alluded to twice since 

 that time by Horn. The following descriptions are based 

 wholly upon these published observations. There is but one 

 described genus as follows : — 



Clypeus produced anteriorly, oblique at the sides, the apex deeply emar- 

 ginate, covering the labrum [LeConte] ; labrum moderately prom- 

 inent, feebly emarginate [Horn] ; eyes feebly emarginate, trans- 

 verse, without supra-orbital carina; mentum large, flat, subpenta- 

 gonal, the apex emarginate ; palpi and antennae wanting in the type 

 specimen [LeConte]; maxillary palpi slender, with the last joint 

 broader ; antennae with the first three joints nearly equal and longer 

 than the others, four to ten gradually increasing in width, com- 

 pressed, wider than long and trapezoidal, the last joint oval, 

 acute and smaller than the preceding [Horn] ; anterior tibiai not 

 at all dilated, the apex truncate [LeConte], with the outer angle 

 prolonged, the tarsi with spinous hairs beneath [Horn] ; mandi- 

 bles obtuse, feebly grooved above, not clasping the middle lobe of 

 the epistoma, allowing the labrum to be partly visible while they 

 are completely invisible from above when folded [Horn] ; pos- 

 terior coxje approximate. Body somewhat elongate, convex, 

 slightly dilated posteriorly [LeConte], very robust, broadly oval, 

 very convex [Horn] ; prothorax and elytra closely joined, the 

 facies somewhat that of Eurymetopon Auchmobius 



If the antennae are properly described above, the necessity for 

 tribal separation of Auchmobius becomes quite evident. 



Auclimobius Lee. 



The single described species is the following, the diagnosis 

 being that of LeConte (Ann. Lye. V, p. 140) : — 



Oblong, somewhat elongate, convex, black, rather shining ; prothorax 

 finely punctulate, more than twice as wide as long, the base trun- 

 cate, the sides slightly rounded ; elytra finely punctate [rather 

 coarsely — Horn], behind the base somewhat broader, narrowed 

 toward apex, strongly declivous and finely, less densely muricate. 

 Length 10. o mm. California (Vallecito) [LeConte] ; Owens 

 Valley and Tejon [Horn] sublaevis Lee. 



