184 CALIFORNIA ACADEMY OF SCIENCES. 



prominent; joints three to eight equal in width, nine to eleven increasing 

 uniformly and rather rapidly in width. Prothorax widest in the middle, 

 where it is scarcely wider than the head, distinctly wider than long; sides 

 very narrowly rounded, convergent and more broadly rounded anteriorly, 

 moderately convergent and rather deeply sinuate toward base; the latter 

 broadly, feebly arcuate, five -sixths as wide as the disk, one-half wider than 

 the apex; the latter transversely truncate; disk strongly convex, not percej)- 

 tibly punctate, broadly impressed before the base toward the sides, trans- 

 versely subgranulose along the base; lateral foveie rather large, deeply im- 

 pressed, at one-third the length from the base; median about equal in size, 

 less deeply impressed. Elytra at base distinctly wider than the prothorax, at 

 apex twice as wide as the latter; sides evenly and moderately arcuate; disk 

 distinctly wider than long, broadly and not strongly convex, more abruptly 

 declivous along the sides; humeri rather prominent; surface excessively 

 feebly and obsoletely punctate; sutural striae fine, deeply impressed, nearly 

 parallel; discal very fine and feeble, slightly arcuate, gradually evanescent at 

 slightly less than one-third the length from the apex. Abdomen polished, 

 impunctate; border strong; carinae of first segment very short, divergent, 

 distant by fully two-fifths the total width. Legs rather long and slender; 

 posterior tibiae feebly clavate, very slightly bent, veiy feebly and obsoletely 

 grooved exteriorly at apex. Length 1.3 mm. 



Texas; (El Paso 1). 



The sole representative is a male, exhibiting the usual 

 very marked abdominal characters. The first segment is 

 very long-, four-fifths as long as the elytra, and is almost the 

 only portion of the abdomen seen when viewed vertically; 

 its apex is rather abruptly deflexed, transversely impressed 

 in the middle; the edge with a small, rounded, very distinct, 

 median sinuation; remaining segments almost vertical, very 

 short, almost equal; second broadly and extremely feebly 

 sinuate in the middle ; surface anteriorly with a transversely 

 arcuate, impressed channel which is partially hidden under 

 the first segment, and which corresponds in outline with the 

 sinuation of the first; remaining segments not sensibly mod- 

 ified. The apical margins of the first and second segments 

 are abruptly thinner. 



This species probably belongs to the Belfragei type, but 

 the description of that species will not apply to this. 



B. infinita n. sp. — Form slightly robust. dark rufo-castaneous; head black- 

 ish; elytra rufous, darker at base and apex; antennae and legs coucolorous, 



