AMERICAN COMPONENTS OF THE TENTYRIIN^ 493 



transverse sulcus ; line of demarkation between the pronotum and 

 propleura) impressed throughout ; prosternum very long before 

 the coxa^ and transversely impressed at al)out llie middle ; scutellum 

 minute but evident, elongate-oval ; elytra not margined at base, 

 not costate but with a flat sutural elevation, feebly embracing the 

 sides of the body, the epipleur;e narrow though entire and with a 

 continuous flat raised line at their lower margin ; abdominal 

 sutures perfectly rectilinear throughout, deep and sulciform, the 

 fifth segment very short, transversely impressed somewhat as in 

 Usechus^ the first segment very long ; coxa; small, the anterior con- 

 tiguous, the middle narrowly, the posterior rather widely, separated ; 

 metasternum long though shorter than the first ventral, the epi- 

 sterna very narrow, linear ; legs rather short, moderately stout, 

 the tibial spurs short but distinct, the hind tarsi stout, cylindric, 

 much shorter than the tibia;, sparselv spinido-setose beneath, the 

 first joint much shorter than the next two combined, the claws 

 small and slender. [Type D. striaticeps Lee] Dacoderus 



I only know this genus from the Sonoran fauna of our extreme 



southwest, though it is said to occur also in the West Indies, 



but, if the latter form, described under the name doniinicensis 



by Horn, is truly endemic, it is probably not strictly congeneric, 



although doubtless assignable to the same tribe. 



Dacoderus Lee. 

 The contiguous anterior cox^ of this genus constitute an ex- 

 ception in the entire family Tenebrionidge, so that its general 

 isolation can be well appreciated, although there are some char- 

 acters, as above defined, that conclusively prove its general 

 position to be in the series of small slender forms allied to 

 Arceoschiziis^ Adelostoma and Stenosis. The transverse sulcus 

 of the pronotum, traceable also as a depression of the prosternum, 

 is remindful of some Histerids ; it is a singular repetition, in the 

 second segment of the body, of the sulcus and tuberosities of 

 the first segment or head, the frontal modifications of which are 

 without a parallel known to me. Our single species is the fol 

 lowing: — 



Body very elongate, parallel, slender and depressed, polished, glabrous, 

 the anterior parts with very few short sparse hairs, dark castaneous 

 in color; head longer than wide, dilated and laterally oculate in 

 basal half, the surface above longitudinally and coarsely plicate, flat, 

 gradually declivous anteriorly to the frontal excavation, canaliculate 

 beneath along the median line, the antennae not quite as long as 

 the head and prothorax, the latter elongate, evidently longer than 



