66 MISC. PUBLICATION 4 7 0, IT. S, DEPT. OF AGRICULTURE 



arcuately expanded behind middle, then arcuately converging to tips, which 

 are separately broadly rounded; lateral margin's not distinctly serrate; basal 

 depressions broad and rather deep; humeral depressions oblong and shallow; 

 surface finely, densely, deeply, uniformly punctate, very sparsely clothed toward 

 apex with short, inconspicuous, erect, white hairs, without distinct discal 

 foveae, intervals densely granulose. Each elytron with indistinct longitudinal 

 costae, which are not smooth, but granulose, the first slightly elevated on apical 

 half, the others barely indicated by short lines. 



Abdomen beneath coarsely, sparsely, irregularly fossulate-punctate, sparsely 

 clothed with short, recumbent, white hairs, without distinct, smooth, lateral 

 callosities, intervals densely granulose; last visible sternite broadly, deeply, 

 arcuately emarginate at apex, the angle on each side of emargination broadly 

 rounded, without a distinct submarginal ridge, lateral margins not serrate; 

 eighth tergite vaguely emarginate at apex, coarsely, confluently punctate, but not 

 longitudinally carinate. Prosternum coarsely, densely punctate, rather densely 

 clothed with long, semierect, white hairs ; anterior margin with a distinct, rather 

 long, median lobe. Anterior femur with a broad triangular tooth, which is not 

 distinctly dentate on outer margin. Anterior tibia arcuate, with a short dilation 

 at apex ; middle and posterior tibiae straight. 



Length 7 mm., width 3 mm. 



Keclescribed from the male lectotype, No. 2707, in the Museum of 

 Comparative Zoology, Cambridge, Mass. 



Female. — Differing from the male in having the front of the head uniformly 

 purplish brown and more sparsely pubescent, the last visible sternite more 

 elongate, and shallowly, arcuately emarginate at apex, the eighth tergite broadly 

 rounded at apex, and the surface sparsely punctured, the prosternum more 

 sparsely punctured and less densely pubescent, and the anterior tibia slightly 

 arcuate and unarmed at apex. 



Type locality. — Fort Riley, Kans. ; lectotype simply labeled with a 

 light-green disk. 



DISTRIBUTION 



From material examined : 



California: Siskiyou County, July-August (A. Koebele). Mt. Rolston, Aug. 6, 



1934 (L. W. Say lor). 

 Kansas: Fort Riley. Type series (John Xantus). 

 Nevada: No definite locality (Horn collection). 

 Wyoming: Yellowstone National Park, July 26, August 1 (Hubbard and 



Schwarz). 



Also recorded in the literature from : 



Colorado: Big Blue Canyon (Wickham 1902). 

 Nevada: Verdi (Chamberlin 1926). 

 New Mexico (Fall and Cockerell 1907). 



Horn (1886) records it from Nebraska, Arizona, and Texas, but 

 the Nebraska record refers to purpurata Bland, and the specimen 

 from Arizona under this name in the Horn collection belongs to 

 another species. No specimens from Texas have been examined by 

 the writer. 



Hosts. — The larval habits are unknown, but L. W. Savior collected 

 the adults at Mt. Eolston flying to and digging into the base of 

 sulphur plants (Eriogonum sp.). 



The color is rather uniform, in the specimens examined, but fre 

 quently the pronotum is slightly sulcate at the middle and the smooth 

 chevron on the front of the head is absent. In the specimens from 

 Mt. Eolston the dorsal surface of the body is more shining, with 

 the pubescence on the elytra slightly longer, the elytral costae more 

 distinct, and the dilation on the anterior tibia of the male not so 



