28o MEMOIRS ON THE COLEOPTERA 



diameters, the two oblique basal striae distinct; pygidium rather strongly 

 and closely punctate; prpsternum convex between the coarse grooves, 

 this part distinctly punctate, divided by a transverse sulcus at basal 

 two-fifths, the basal part slightly more depressed and less punctate than 

 the apical part, the lateral ridges also impressed in line with the sulcus; 

 post-sterna canaliculate along the median line and with an oblique 

 coarse groove at each side; anterior tibiae feebly dilated and with a few 

 external setae in less than apical half. Length 1.35-1.4 mm.; width 0.68 

 mm. California (Calaveras Co.). Two examples. 



Differs from fraternus in its somewhat larger size and less slender 

 form, less medially divided prosternum, with much broader pos- 

 terior lobe, this being very narrow in fraternus, also in the very 

 much more strongly and closely punctate head, which is noticeably 

 concave between the eyes, though feebly so. Molestus Csy., from 

 Lake Tahoe, is smaller and has very much more strongly and 

 densely punctate elytra, but the small and very narrow posterior 

 lobe of the prosternum is more nearly as in fraternus, which has 

 still more sparsely punctate elytra than in egenus. 



Plegaderus Convergens n. sp. Short and stout, rather convex, obscure 

 ferruginous, the elytra more blackish; head finely, very sparsely punc- 

 tate, feebly impressed on the median line basally; prothorax two-fifths 

 wider than long, the sides parallel basally, unusually gradually rounding 

 inward anteriorly, the lateral groove deep, attaining the base, the mar- 

 ginal surface well developed, closely punctured; disk divided by a deeply 

 impressed, transverse and posteriorly arcuate groove, very little before 

 the middle of the length; both lobes convex and with fine, sparse and 

 equal punctures, which are however a little larger basally; elytra shorter 

 than wide, a third longer than the prothorax, broadly and moderately 

 inflated subbasally, the sides thence very strongly converging and broadly 

 arcuate to the apex, which is much narrowed; surface with coarse, dense 

 and deep punctures equally throughout, the oblique basal striae obsolete; 

 prosternum with extremely deep longitudinal grooves, the intermediate 

 surface distinctly punctate, the dividing sulcus post-median, the basal 

 lobe narrower as well as shorter than the anterior; anterior tibiae feebly 

 dilated apically, and there having a loose external fringe of short stiff 

 setae. Length 1.2-1.35 mm.; width 0.65-0.77 mm. Colorado (Boulder 

 Co.). Two examples. 



The types represent a species, not closely allied to any other, 

 being distinguished by its short, stout form and very strongly 

 apically narrowed and densely, coarsely cribrate elytra; it may be 

 placed near cribratus among the species already described. 



*Plegaderus densus n. sp. father stout, only moderately convex or 

 shining, dark castaneous in color, the legs more rufous; head finely but 

 deeply, not very closely punctate; prothorax two-fifths wider than long, 



