374 BULLETIN G3, UNITED STATES NATIONAL MI^SEUM, 



Affendage very short maminilliforin, with three or four long hairs 

 at tip; fossa on the basal and external surface of apex, small. 



Superior inidendal memhrmie long, attaining the apical sixth of 

 the dorsal plate and longitndinally rugnlose. 



Basal jproniinences not evident, evenh^ rounded about base. 



Ventrolateral surfaces. — Body quite evenly convex from side to 

 side, surface lines straight when viewed longitudinally, feebly con- 

 cave laterally before the apex; apex finely setose. Submarginal 

 groove distinct and moderate beneath the very narrowly prominent 

 external margin of the dorsal plate. Internal margins of the valves 

 contiguous in basal third ; fissure rather long and quite narrowly 

 fusiform; inferior pudendal membrane not visible. 



Hahifat. — California (common about the sand dunes under vege- 

 tation, along the coast of central California ; Doctor Horn reports 

 it as extending northward to the head of the Sacramento Valley; as 

 far south as Los Angeles County). 



Xumber of specimens studied, 600. 



Tyi^e in the Eschscholtz collection. 



Type-locality. — California near San Francisco, 



Salient type-characters. — Oblong-ovate, Antenna? slender and 

 subclavate. Pronolal disc not noticeably transverse, arcuately de- 

 clivous laterally, with moderately long erect setae on the declivous 

 portions; apical angles obtuse, feebly rounded; sides rather evenly 

 rounded, rather straight and converging posteriorly, just the least 

 sinuate before the basal angles. Elytra coarsely punctate, with slight 

 evidence of a serial arrangement when viewed longitudinally, 

 sides more irregularly and subnuiricately punctate. The punctures 

 are setigerous throughout. 



Diagnostic characters. — Clavtcornis is a very distinct species and 

 quickly recognized by its small size and setose sides of the pronotal 

 disc. No other species of the subgenus Blapylis has the propleurre 

 so distinctly pubescent. Scahros(t is the most closely related species, 

 and differs in its distinctly larger and transverse pronotum, the discal 

 sides of which ai'e not in the least declivous, although set with rei-y 

 short erect scta\ Clavicornis has tlie elytra rather coarsely and 

 densely punctate, the punctures are impressed, the sculpturing is 

 quite bkc that observed in scabrosa. 



The punctures are noticeably setigerous throughout. The antemuv 

 are usually feebly clavate. 



The species named l)y Boheman as rmpressi colli s is simply speci- 

 mens which have two thoracic fo\'eie. Such accidental variations 

 are common (see ]). 27) ; sometimes only one foNca is ])resent ; this 

 variation is fi-e(|uently observed in othei- species. 



