278 MEMOIRS ON THE COLEOPTERA 



intervals broadly convex. Length (cf) 6.2 mm.; width 2.4 mm. 

 New York (Lake Champlain) nupta n. sp. 



Form less slender; thoracic sides more arcuate, converging anteriorly 

 from behind the middle, the prothorax often inflated and sometimes 

 wider than the elytra 5 



5 Prothorax inflated, wider than any part of the elytra. Body elon- 

 gate-oval, convex, highly polished throughout and rufo-castaneous, 

 the under surface paler, rufous, the legs flavo-rufous; head with 

 moderately prominent eyes and short feebly impressed and stib- 

 foveiform strioles; antennae long, ferruginous, extending to the mid- 

 dle of the body, rather thick, the joints very strongly obconic; 

 prothorax two-fifths wider than long, the sides strongly arcuate; 

 apex very narrow, four-sevenths as wide as the base, deeply sinuate 

 and with prominent though bluntly pointed angles, widest well 

 behind the middle, the margins very finely and not strongly re- 

 flexed; basal angles obtuse, not rounded, the moderate puncture 

 nearer base than side; impressions obsolete, the stria deep, entire; 

 punctures of the foveal regions few, very coarse and widely dis- 

 persed; inner fovea large, broadly impressed, oblong, the outer 

 smaller, irregular; elytra nearly one-half longer than wide, barely 

 twice as long as the prothorax and slightly narrower, gradually 

 ogival behind the middle; striae rather coarse, very deeply impressed, 

 strongly punctured internally, almost completely impunctate ex- 

 ternally, the scutellar short, free and entire; intervals everywhere 

 strongly convex. Length (cf) 6.3 mm.; width 2.65 mm. Colo- 

 rado (Boulder Co.) thoracica n. sp. 



Prothorax sometimes perceptibly inflated but nowhere wider than the 

 elytra 6 



6 Oblong-suboval, convex, piceous-black, very faintly subaeneous, pol- 

 ished, the elytra frequently deep black and always with faint alu- 

 taceous lustre in the female; under surface piceous-black, the legs 

 bright rufous; head very small, much less than half as wide as the 

 prothorax, the eyes only moderately convex; strioles short, linear 

 and oblique; antennae long and slender, extending far behind the 

 thoracic base in the male, pale ferruginous; prothorax a third to 

 two-fifths wider than long, the apex narrow, deeply sinuate; sides 

 broadly arcuate, moderately reflexed; basal angles scarcely more than 

 right and not rounded; transverse impressions feeble, the anterior 

 close to the sinus; punctures of the foveal regions rather sparse, 

 moderate and not very numerous; foveae distinctly impressed, the 

 inner linear, the outer irregularly rounded, with the external bor- 

 dering surface rather prominently convex; elytra nearly one-half 

 (cf ) to two-fifths (9 ) longer than wide, equal in width to the pro- 

 thorax (cf) or just visibly wider (9 ), the sides feebly arcuate; apex 

 very gradually ogival; striae not coarse but rather deeply impressed, 

 distinctly but not coarsely punctate, the scutellar moderate, gen- 

 erally entire; widely free at tip; intervals broadly and subsimilarly 

 convex in both sexes. Length (cf 9 ) 5.4-6.5 mm.; width 2.5-2.75 

 mm. Lake Superior (Marquette and Duluth). Very abundant. 

 Thirty-one specimens subaenea Lee. 



