392 Coleopferological Notices, V. 



feebly elevated bisinuate subapical elevation, and the seventh is 

 deeply, almost equally and angularly biemai'giuate. 



O. niger Lee— Trans. Am. Ent. Soc, VI, 1877, p. 235. 



Parallel, rather narrow, somewhat convex, polished, black 

 throughout, the antennae not at all paler at base; legs dark red- 

 dish-brown. Head slightly transverse, convex, a little narrower 

 than the prothorax, impressed only at the inner side of the anten- 

 nal prominences, the frontal margin finely beaded, transversely 

 truncate; punctures fine but strong, not dense; eyes very small; 

 tempora large, rounded, more prominent than the eye ; antennae as 

 long as the head and prothorax, feebly incrassate, the basal joint 

 long, cylindrical, narrowed gradually toward base, tenth very 

 slightly transverse, eleventh nearly as long as the preceding two. 

 Prothorax two-thirds wider than long, narrowed behind from near 

 the apex, trisulcate, the median sulcus deeper, scarcely impressed 

 toward the sides, not very coarsely but strongly, sparsely punctate. 

 Elytra equal in width to the prothorax but not quite as long, rather 

 coarsely but sparsely punctate, somewhat uneven. Abdomen very 

 remotely and obsoletely punctulate, rather coarsely so and distinctly 

 pubescent beneath. Length 3.3 mm.; width 0.75 mm. California 

 (San Francisco and Lake Tahoe) ; British Columbia — LeConte. 



The sixth ventral plate of the male is obtusely tuberculate at its 

 centre, and also has, on the disk near the posterior edge, two small 

 erect very approximate tubercles arranged transversely, the seventh 

 broadly biemarginate, the median lobe broadly rounded, the eighth 

 not longitudinally impressed. The mentum is transverse, shining 

 though transversely rugulose, impressed along the basal margin, 

 and with the usual pale semi-membranous apical piece. 



O. placiisimis Lee. — Trans. Am. Ent. Soc, VI, 1877, p. 237. 



Pale reddish-brown throughout, the head and abdomen more 

 piceous but only slightly darker ; punctures rather coarse, very 

 dense, forming long anastomosing rugae, the depressed flat front of 

 the head between the antennal prominences shining, almost im- 

 punctate; tergum subimpunctate but strongly reticulate and dull 

 toward base; integuments glabrous, the tempora, and especially 

 the venter, distinctly pubescent. Head narrower than the protho- 

 rax, as long as wide, subquadrate ; eyes small, convex, at the 

 middle ; antennae feebly incrassate, one-half longer than the head. 



