142 MEMOIRS ON THE COLEOPTERA 



the carinae entire; antennae piceous-black throughout, moderately long, 

 notably thick but not much increasing from the third joint to the tip, 

 the third scarcely at all longer than the second, very strongly and evenly 

 obconic, fourth very slightly longer than wide, fifth fully as long as wide, 

 six, seven and ten but slightly, the eighth and ninth shorter and more 

 strongly, transverse, the last fully as long as the two preceding; prothorax 

 moderate, nearly one-half wider than long, parallel and strongly, sub- 

 evenly rounded at the sides, the median line very obsoletely impressed, 

 enlarging sensibly at base; elytra at base fully a sixth wider, the suture 

 two-fifths longer, than the prothorax; abdomen evidently narrower than 

 the elytra, just visibly tapering and with straight sides throughout, the 

 fourth and fifth tergites equal, the sixth (e?) with two short subtuber- 

 culose median teeth, which are mutually a little more approximate 

 than either from the lateral processes, the latter moderate. Length 2.8 

 mm.; width 0.75 mm. California (Saucelito, Marin Co.). 



Recognizable at once by the antennal structure, the tenth joint 

 being notably longer than the eighth or ninth. 



Dimetrota opinata n. sp. Coloration and sculpture nearly as in the 

 preceding, except that the legs are pale brown throughout; head smaller, 

 but little wider than long, three-fifths as wide as the prothorax, the eyes 

 slightly prominent, at about their own length from the base, the tempora 

 equally prominent, straight for some distance, the carinae entire; antenna? 

 moderately long, piceous-black throughout, rather slender basally, very 

 gradually and evenly incrassate to the tip from about the third joint, 

 which is obconic and just visibly longer than the second, fourth only as 

 long as wide, similar to the fifth, sixth to ninth equal in length but in- 

 creasing from nearly as long as wide to distinctly transverse, the tenth de- 

 cidedly longer and less transverse, the last as long as the two preceding; 

 prothorax as in the preceding throughout but a little shorter; elytra 

 at base about a fifth wider, the suture two-fifths longer, than the protho- 

 rax; abdomen as in the preceding, except that the sixth tergite (cf ) has 

 the two median teeth at tip smaller though more acute and mutually 

 separated by exactly the interval between each and the lateral processes, 

 with the edge between them transverse and not sinuate as it is in in- 

 credula. Length 2.75 mm.; width 0.72 mm. California (Berkeley, 

 Alameda Co.). 



Differs from the preceding in its slightly smaller head and pro- 

 thorax, more basally tapering antennae and in the conformation of 

 the apex of the sixth tergite in the male. 



Dimetrota cerebrosa n. sp. Black, the anterior parts alutaceous and 

 feebly bronzed, the elytra pale, blackish about the scutellum, the abdomen 

 strongly shining; sculpture as in the preceding, the asperate punctures 

 small and dense, the abdomen sparsely punctulate posteriorly; head 

 distinctly transverse, nearly three-fourths as wide as the prothorax, 

 the eyes moderately convex, at nearly their own length from the base, 

 the tempora straight and parallel, rounding basally, barely as prominent 



