IjCConte] 



BARIXI. 295 



Interspaces of elytra with rows of punctures 2. 



Interspaces of elytra densely punctured, and thinly pu- 

 bescent 1, densa. 



3. Prosternum very wide between the coxse 3. 



" moderately wide between the coxse 5. 



3. Black, glabrous, or nearly so 4. 



Dull black, finely pruinose 2. subtonsa. 



4. Prothorax without smooth dorsal line 3. pectorosa . 



" with broad dorsal line 4. distans; 



Much smaller and narrower 5. seriata. 



5. Sparsely pubescent; very coarsely cribate 6. cribrata. 



Prothorax plicate, elytra with pattern of large narrow 



scales 7. rugicollis. 



1. O. densa (Lee), Pr. Acad. Nat. Sc. Phil. 1859, 79; ibid. 1868, 3G?. 

 San Diego, Cal., three specimens. Broader and less finely pubescent 



tlian 0. subtonsa, with the prothorax more coarsely punctured and subra 

 rinate; it is gradually narrowed in front from the base for two-thirds t e' 

 length, then rapidly narrowed to the apex, which is distinciy constriced. 

 Head punctured in front, smooth behind. Striae of elytra deep, in'erspaces 

 flat, irregularly punctured. Beak as long as prothorax and not stout; club 

 of antennae oval, entirely pubescent and sensitive. Front coxse widely 

 separated, prosternum flat, densely and coarsely punctured. Length 4 mm. ; 

 .16 inch. 



2. O. subtonsa, n. sp. 



Less robust, dull black, pruinose with very fine whitish pubescence, 

 more evident on the elytra than on the prothorax. Head punctured in 

 1: jnt, nearly smooth behind, beak longer than in the preceding. Prothorax' 

 scarcely wider than long, sides parallel for two-thirds the length, than rap- 

 idly narrowed and rounded to the apex, which is feebly constricted at the! 

 sides: disc densely punctured, each puncture with a small hair a* the bot- 

 tom; antescutellar lobe broad, not emarginate. Elytra scarcely wider than 

 the prothorax, striae deep, interspaces flat, each with a row of small punc- 

 tures. Front coxae widely separated; prosternum nearly flat. Length 

 4 mm.; .16 inch. 



Texas, Belfrage, one specimen. \ 



3. O. pectorosa, n. sp. 



Ovate, narrower behind, black, nearly glabrous above. Head sparsely 

 punctulate; beak as long as the prothorax; rather sLmder, punctulate, 

 much curved at base, frontal constriction deep. Prothorax larger than 

 usual, wider than long, slightly narrowed from the base for two-t'iirds the 

 length, then rapidly narrowed to the tip, which is constricted at the sides; 

 disc rather closely but not coarsely punctured; scutellar lobe m )r.! promi- 

 nent than usual, truncate. Elytra at bas' not wider than proth )rax, grad- 

 ually narrowed behind; striae deep, interspaces flat, each with a row of 



