Platynin.e 51 



mm. California (Hoopa Valley, Humboldt Co. and also in Siski- 

 you Co.). Fifteen examples cornicula n. sp. 



Form somewhat less stout, more elongate and a little more convex, 

 distinctly larger in size, deep black and polished throughout in both 

 sexes; head and antennae nearly as in the preceding; prothorax 

 slightly less transverse, about a fourth wider than long, not quite 

 so narrowed basally; sides legs arcuate, becoming sinuate and sub- 

 parallel basally, finely reflexed, only very little more so at base and 

 not there broadly reflexed as in cornicula; basal angles right and 

 very sharp, sometimes minutely subprominent; base fully as wide 

 as the apex and relatively broader than in the preceding; surface 

 with rather strong transverse fugulae and distinct anterior im- 

 pression; fovea? deep, concave, strongly rugose, disappearing at 

 about the middle; apex rather deeply sinuate, with well defined 

 angles as in cornicula; elytra more elongate and larger, though not 

 quite one-half longer than wide, more gradually rounding behind, 

 four-fifths wider than the prothorax; humeri rapidly rounded; 

 subapical sinus but slightly oblique and very shallow; stride grooved,' 

 not so fine as in the preceding and deeper, nearly smooth; intervals 

 flat, not quite so polished as in the preceding, the three punctures 

 similar; anterior male tarsi feebly dilated, less so than in cornicula; 

 met-episterna twice as long as wide. Length (i2cf, 2?) 6.8-7.8 

 mm.; width 2.7-3.1 mm. Nevada (Reno). Male much more 

 abundant than the female as in the preceding species. 

 „ renoanus n. sp. 



l^orm much more abbreviated and very small in size, rather convex, 

 similarly deep black and rather shining; head smaller, barely 

 longer than wide, three-fourths as wide as the prothorax, with 

 moderate and rather prominent eyes; antennae slender but shorter; 

 prothorax short and transverse, almost one-half wider than long! 

 sides inflated and strongly arcuate anteriorly, oblique and straight 

 or just visibly sinuate in basal half, finely reflexed throughout, the 

 angles obtuse but with sharp tips; base as wide as the broadly' and 

 deeply sinuate apex; rugulaj and anterior impression feeble; foveae 

 short, scarcely at all impressed, not extended anterioriy and strongly 

 rugose; elytra short, two-fifths longer than wide, four-fifths wider 

 than the prothorax, convex, oblong-suboval, rounding gradually 

 behind the middle; humeri not quite so rapidly rounded; subapical 

 sinus, striae and flat intervals neariy similar; tarsi slender. Length 

 (9 ) 6.4 mm.; width 2.65 mm. Nevada (Reno). One specimen. 



parvus n. sp. 

 l^orm narrower, rather more convex, even more strongly shining than 

 in any of the preceding three species, deep black throughout, with- 

 out trace of metallic lustre; head barely longer than wide, neariy 

 four-fifths as wide as the prothorax, with very prominent eyes, 

 the impressions linear, moderate; surface very smooth; antenna 

 deep black, very slender, slightly over half as long as the body, the 

 third and fourth joints equal; prothorax neariy two-fifths wider 

 than long, widest and with strongly rounded sides before the middle, 

 the sides oblique and just visibly, broadly sinuate behind, the 



