466 CALIFORNIA ACADEMY OF SCIENCES. 



the apex sliglitly less than twice as wide as the latter; disk distinctly wider 

 than long, moderately convex; sutural stvise strong, nearly straight, conver- 

 gent and arcuate near the apex; discal fine, feebly impressed feebly sigmoid, 

 becoming obsolete at one-fifth the length from the apex. Abdomen slightly 

 shorter and very little narrower than the elytra; sides nearly straight and 

 parallel; border moderate in width; surface broadly and feebly convex; first 

 segment, the only one seen when viewed vertically, nearly five-sixths as long 

 as the elytra. Legs slender. Length 1.2 mm. 



Arizona (Tucson 1). 



Described from the male, the sexual characters being simi- 

 lar in form to those of texana, but having the median tuber- 

 cle of the second segment smaller, less transverse and much 

 more prominent. 



This species belongs to the texana group of the genus, 

 which is distinguished by the great development of the first 

 ventral segment in the male, this being the only part of the 

 abdomen seen when viewed vertically. It differs from texana 

 in its smaller size, slightly more robust form, much shorter 

 elytra, narrower abdominal border, in the size and position 

 of the pronotal foveae, and in its shorter antennae with less 

 prominent club; the eighth, ninth and tenth joints in texana 

 are much less transverse. In texana the median fovea of 

 the pronotum is larger, and at about one-fourth the length 

 from the base, the three foveas being more nearly on a trans- 

 verse line than in arizonm. 



NISAXIS Casey. 



N. cincinnata u- sp- — Slightly robust, clear testaceous throughout; legs 

 and antennae slightly paler; pubescence moderately dense, rather long. Head 

 very slightly narrower than the prothorax, as long as wide; eyes rather large, 

 prominent, at two-thirds their own length from the base; genee very feebly 

 convergent toward base, feebly arcuate, not at all prominent; base trans- 

 versely truncate; front large, quadrate, fet-bly convex, coarsely, deeply, not 

 densely punctate, impunctate in the middle, feebly biimpressed near the 

 vertex; antennae about as long as the head and prothorax together, first two 

 joints nearly equal, slightly more robust, one-half longer than wide, nearly 

 cylindrical, third obconical, longer than wide, much shorter than the second, 

 as long as the fifth, longer than the fourth, sixth aud seventh slightly shorter, 

 very little longer than wide, eighth very slightl}^ wider, a little wider than 



