LECONTE ON EOCKY MOUNTAIN COLEOPTERA. 479 



ate behind ; front angles prominent, subacute ; hind angles obtuse, not' 

 rounded ; side-margin narrow, reliexed, base truncate ; transverse im- 

 pressions deep, longit-udinal line strongly impressed, basal impressions 

 deep, not punctured. Elytra a little wider than the prothorax, sides 

 nearly parallel, humeri broadly rounded 5 striae fine, feebly punctured, 

 outer ones nearly effaced ; three or four dorsal punctures on the 3d 

 stria. Last ventral segment rufo-piceous (from the immaturity of the 

 specimen). Length 11'"™ (0.43 inch). 



Green Eiver City, Wyo., (6,000-7,000 feet) ; Mr. Bowditch. This spe- 

 cies closely resembles N. Eschscliolzii from Alaska, Vancouver, and Brit- 

 ish Columbia, and has equally long legs and antennae. It differs, how- 

 ever, by the sides of the prothorax not sinuate towards the base, with the 

 hind angles obtuse ; and by the elytra being less convex, more oblong, 

 with the sides more nearly parallel, and not wider behind. 



The geographical distribution of these groups may be recapitulated 

 as follows : — « 



Group I. — Two species from high mountains of the Sierra Kevada^ 

 and one from lower levels, near the Pacific coast. 



Group IL — Two species from high mountains of Colorado ; one from 

 Sierra Nevada, nearly allied to them ', a smaller one {N. carhonaria), less 

 similar, from the Alaskan Islands and Kamtschatka, but somewhat 

 resembling N. siituralis of Group IV. 



Group III. — Two Alaskan species, extending to Vancouver and Brit- 

 ish Columbia. 



Group IV, — Of this group, five are Alaskan, one of which, A\ Geb- 

 leri, extends to Vancouver ; one, N. Scihlbergii, extends over the whole 

 hyperborean region of North America, from Alaska to Canada, south- 

 wards to Vancouver on the western coast, and has left a post-Glacial col- 

 ony on the White Mountains in New Hampshire; two others, JSF. suturalis 

 and hudsonica, are hyperborean ; they do not extend to Alaska, but the 

 former has left a colony on the White Mountains, and the latter occurs 

 from the Saskatchewan to Newfoundland ; another, JV". nivalis, a North- 

 ern European species, is found in Iceland and Greenland, but as yet has 

 not occurred on the mainland of this continent ; it is very closely allied 

 to N'. hudsonica, differing chiefly by the more prominent hind angles of 

 the prothorax and by the red legs. The remaining three are from the 

 mountains of Colorado, and one of them seems near to N. suturalis^ 

 while the other two, JV". ohliqua and ohtusa, are rather isolated, and per- 

 haps only Color varieties of one species. 



Group V. — Contains a very peculiar isolated species from the coast 

 region of California and Vancouver Island. 



Group VI. — Contains an equally isolated species from the Atlantic 

 slope of the continent, from Canada to Georgia and Minnesota to Nova 

 Scotia. 



If we disregard the color of the antennae, palpi, and legs as having 

 no specific value, a certain reduction in the number of species may be 



