168 Journal New York Entomological Society. [^^°'- xxx. 



or sometimes not at all, tumid just below the middle. Margins of clypeus 

 rather strongly but not abruptly elevated, the lateral margins nearly as promi- 

 nent as the anterior, and separated from it by a poorly defined or obsolete 

 notch ; anterior portion of clypeus wider than usual, with prominent but 

 strongly rounded corners, the reflexed margin viewed perpendicularly broadly 

 and moderately arcuate at the middle, viewed at an angle from above nearly 

 straight ; puncturation of clypeus moderately strong and dense, the punctures 

 separated by their own diameters or less. Front a little less regularly and 

 closely punctured, and occipital area impunctate. Antennae and eyes of 

 average size. Measurements of head: diameter of head through eyes, 19; dis- 

 tance between inner eye margins, ii-S; length of head on median line, 13; 

 extreme width of clypeus at the point of the nearly obsolete incisure, 6.5 ; 

 antenna! club, 7 ; dorso-ventral diameter of eye, 6. 



Pronotum, transversely, more convex than usual, the sides evenly and 

 rather strongly rounded from base to apex. Surface evenly covered with 

 moderate-sized punctures, separated by one to two times their own diameters. 

 A small piceous spot just above the side margins of the pronotum, distinct 

 on pallid specimens, but discernible even on the darkest ones. Measurements 

 of pronotum : greatest width just in front of the rounded posterior angles, 

 31; width through the obtuse anterior angles, 19; length on median line, 19. 

 Scutellum punctured like the pronotum ; length. 8 ; greatest width, 8. 



Elytra with moderately impressed, line-like strise, each stria having a single 

 row of rather small punctures, separated by about their own diameters. 

 Puncturation of the intervals rather fine, sparse, and irregular, the punctures 

 often more closely placed adjoining the lines of strial punctures. The inter- 

 vals but slightly convex, sometimes nearly flat, the second, fourth and sixth 

 a little wider than the others. Length of elytra, 54; greatest width, 37- 



Metasternum, posterior coxal plates and hind femora with the usual 

 moderately strong, closely placed punctures. Abdominal sternites very finely, 

 sparsely punctured, and devoid of hair except for the rather conspicuous 

 single rows of erect setae. 



Genital armature of male (PI. XXIII) 2-3 mm. in length. 



O. Differs from the male in having slightly smaller antennae, and the 

 usual more robust form of the abdomen. 



Specimens examined : 67 (^, 20 5. 



North Dakota : Morton Co., i (^. 



Nebraska: Monroe Canyon, Sioux Co., Hc^; Pine Ridge, Dawes Co., 

 2(^; "Valley of the Platte" (Nebraska?), 2 <^, Le Conte's types. 



Colorado: Durango, i (^ ; Pagosa Springs, i c?. 



California : Mill Valley, Marin Co., i (^. 



Nevada : 5 J*. 



Utah : Eureka, 3 c?, 7 ?• 



Montana: Havre, 5 (^ ; Missoula, i J'. 



Idaho: i (^; Coer d'Alene, i $. 



Oregon : Hood River, 2 ^. 



