308 CALIFORNIA ACADEMY OF SCIENCES. 



but not I'ounded; apex and base broadly, rather strongly and equallj^ arcuite; 

 disk nearly oue-thii'd wider than long, moderately and evenlj'^ convex, ratlier 

 coarsely and closely punctate. Elytra at base aboirt one-fourth wider than 

 the prothorax; sides very feebly divergent posteriorly and very feebly arcu- 

 ate; together very slightly wider than long, truncate posteriorly, feebly 

 sinuate at the sutrare and more strongly so near each exterior angle; disk 

 about one-fourth longer than the pronotuin, feebly convex, very coarsely and 

 rather densely punctate; pnnctui-es somewhat asperate. Abdomen slightly 

 narrower than the elytra; sides parallel; border strong; basal segment very 

 coarsely and densely piinctate, each segment being successively more feebly 

 and sparsely punctate, sixth finely and ver}' sparsely so; underside slightly 

 more finely punctate than the upper. Legs rather long, slender; first joint 

 of the posterior tarsi as long as the next three together. Length 2.9- 

 3.2 mm. 



California (Hoopa Yal., Humboldt Co.) 



I found tins very well-marked species to be gregarious 

 and exceedingly plentiful under the fungous bark of a de- 

 cayed log. The pubescence is fine, rather sparse, and not 

 conspicuous. The mesosternal carina is strong, and is a 

 posterior continuation of the reflexed apical margin. 



Tlie type is described from the female; in the male the 

 third antenual joint is very much longer than the second. 



In this genus the head beneath has a very strong infra- 

 ocular ridge, proceeding from the outer posterior angle of 

 each maxillary fissure, to the posterior margin of the head, 

 feebly arcuate and gradually ascending. 



I. nigrinUS n- sp.— Blacksh-piceous; two basal joints of the antenna?, a 

 small humeral spot extending nearly to ihe scutellum, and legs paler, piceo- 

 testaceous, the apices of the abdominal segments especially beneath are also 

 narrowly paler; pubescence very fine, recumbent, not very dense. Head 

 scarcely longer than wide; front moderately convex, very finely, feebly and 

 sparstly punctate; eyes moderate, having excessively fine, short and erect 

 setae; antennas slightly longer than the head and pronotnm together, rather 

 slender, moderately incrassate; basal joint short, scarcely one-third longer 

 than the second, the latter about equal in length to the third, fourth very 

 slightly longer tli/in wide, joints five to ten transverse, eleventh ovoidal, 

 acuminate, slightly shorter than the three preceding together; labrum more 

 than twice as wide as long, truncate, sides parallel. Prothorax widest 

 slightly before the middle where it is just visibly wider than the head and 

 scarcely one-fourth wider than long; sides rather strongly arcuate anteriorly, 

 feebly sinuate just before the posterior angles which are therefore slightly 



