324 CALIFORNIA ACADEMY OF SCIENCES. 



front of them being deeply sinuate for a very sbort distance; disk strongly 

 and coarsely scabrous, feebly convex in the middle, where there is a narrow 

 canaliculation, growing dee^jer toward base, broadly impressed along each 

 side near the margins. Elj^traat base as wide as the prothorax; sides nearly 

 parallel and moderately arcuate near the humei-i; outer apical angles broadly 

 rounded; inner narrowly rounded; together slightly longer than wide and 

 very slightly more than twice as long as the pronotum; disk transversely 

 and moderately convex, feebly and coarsely scabrous, indistinctly, feebly and 

 sparsely punctate. Abdomen very short behind the elytra, triangular, wider 

 than the elytral apices, coriaceous, dull, obsoletely and sparsely punctate; 

 the apices of the segments paler; border evident near the elytra. Legs slen- 

 der. Under surface of the ab lomen shining; segments very short, each with 

 one or two transverse discal rows of very minute setigerous punctures. 

 Length, 1.6 mm. 



California (Santa Cruz, 5). 



The description is tak^n from the male, in which the sixth 

 segment of the abdomen is narrowly and deeply sinuate at 

 the apex, the sinus being strongly rounded at the bottom 

 and slightly wider than deep; the fifth is broadly and 

 strongly emarginate throughout its width, partially enclosing 

 the sixth; the seventh is deeply divided; in the female the 

 sixth segment is deflexed at tip and acutely triangular. 



The species belongs near sidcatus ^a^^v., which is also 

 from California. The antennae from the second joint are 

 almost precisely similar in structure to the prevailing type 

 in the Trichopterygidae. 



ACTIDIUM Matth. 



A. robustulum n- sp. — Form somewhat robust, rather convex. Body 

 black throughout; antennre piceous-browu; legs dark yellowish-browu ; tarsi 

 paler, fiavate; pubescence very short, recumbent, rather dense, cinereous- 

 brown in color; integuments feebly shining, very finely, feebly and somewhat 

 densely granulose. Head nearly twice as wide as long, evenly and mode- 

 rately convex; eyes small but rather prominent, very coarsely granulated; 

 epistoma rather narrow, broadly and very feebly sinuate at apex; labrum 

 much longer than wide, acutely rounded at apex, vertical or felightly inflexed; 

 antennne distinctly longer than the head and pz-othorax together, joints of 

 club increasing in length and thickness. Prothorax slightly less than twice 

 as wide as long, slightly longer and wider than the head; sides parallel and 

 evenly arcuate; anterior angles viewed laterally narrowly rounded, basal 

 more broadly so; base broadly and strongly rounded behind over the bases 



