252 CALIFORNIA ACADEMY OF SCIENCES. [96] 



sternum being not at all depressed or impressed, and divided 

 from the metasternum by a very feeble straight suture. 



Ditaphrus is related to Bothriophorus Muls., but is very 

 -distinct in antennal structure and in the form of the prester- 

 num, this not being broadly emarginate at apex, nor "pos- 

 te'rieurement retrdci en point," as in the latter. From Phy- 

 :semus Lee. it is apparently distinguished by its antennal 

 structure. 



D. SCymnoideS n. sp.— Form elliptical, distinctly longer than wide, con- 

 vex, black; under surface, legs aDd antenna? fuscous; integuments alutaceous; 

 pubescence fine, pale, short, subrecumbent, rather dense. Head rather 

 small, wider than long; surface broadly, evenly convex, finely, deeply and 

 densely punctate; punctures coalescent and scabrous at base; antennae aslong 

 as the width of head; occiput margined laterally along the eyes with a nar- 

 row impressed channel for the reception of the antennas which joins the deep 

 apical excavation of the pronotum. Prothorax about three times as wide as 

 long; sides convergent anteriorly, feebly arcuate; base broadly arcuate, ab- 

 ruptly more strongly so in the middle; apex broadly emarginate; surface 

 broadly convex, very minutely, deeply, evenly, not very densely punctate; 

 punctures separated by three or four times their own diameter. Scutellum 

 slightly longer than wide. Elytra, viewed vertically, nearly three times as 

 ongas the head and prothorax together, widest at one third the length from 

 the base; sides strongly arcuate, coarctate with those of the pronotum, evenly 

 rounded to the apex which, conjointly, is rather narrowly rounded; surface 

 ■strongly convex, rather finely, evenly, deeply and moderately densely punc- 

 tate; punctures decidedly larger than than tho.se of the pronotum, distant by 

 two to three times their own diameters. Legs short; tarsi slightly reflexed. 

 Under surface alutaceous and minutely punctate; abdomen finely, rather 

 densely pubescent. Length 0.8-1.0 mm. 



Texas; (Austin 11; El Paso 1). . 



Rather abundant amongst decaying vegetable matter on 

 the soft mud left hy the receding water of the Colorado 

 River. The antenna is figured on the plate and is seen to 

 be of very singular structure. The club in Physemus, the 

 only genus with which this can be confounded, is described 

 as being three-jointed and almost solid. It is also highly 

 probable that Physemus is distinct from Bothriophorus. 

 These three genera should be separated as a group distinct 

 from Limnichus. 



