32 AMERICAN COLEOPTKRA. 



ever, intergrade in the large series before me. One of the more 

 important variations is to be seen in the prothorax, the sides of 

 wliich are in some examples arcuate from apex to base, the hind 

 angles being very obtuse or almost rounded, while in others the sides 

 are arcuate to behind the middle, from thence oblique to the hind 

 angles, or, in one or two specimens, with a very feeble trace of sinu- 

 ation immediately in front of them, the angles being obtuse and not 

 prominent. The elytral strire vary in depth as well as in the coarse- 

 ness of their punctation, while the intervals vary from flat to feebly 

 convex. The color varies from uniformly black to bicolored, the 

 head and thorax being black and the elytra more or less brownish, 

 sometimes uniformly reddish-brown, sometimes with the sutural and 

 lateral margins dark, and sometimes piceous, only slightly paler 

 than the head and thorax. Much the same range of variation may 

 be observed in the color of the legs, as stated in the description, 

 while the hind tarsi vary from very feebly to not at all grooved on 

 the outer side. These variations are so intermingled that it has 

 been found impossible to separate even varieties by characters of 

 any constancy. 



The species is most closely related to e-schscholtzl and melanogas- 

 trica, but is readily distinguishable from both by the obtuse hind 

 angles of the thorax. 



Nearly three hundred examples have been studied. 



It occurs in Labrador, on Mt. Katahdiu, Maine, Mt. Washing- 

 ton, New Hampshire, Mt. Mansfield, Vermont, in the Hudson Bay 

 region, at high altitudes in the Rocky Mountains of Colorado, in 

 Alaska, extending northward to Point Barrow, and on St. George's 

 Island and St. Paul's Island in Behring Sea. 



16. A, infausta, Lee. — Ftn-m obloiifr, moderately elongate, convex. Color 

 uigropiceous. Head scarcely narrower than the thorax at apex ; frontal grooves 

 short, not extending forward on to the epistoma ; antennse slender, scarcely as 

 long as the head and tiiorax, rufous; pal])! rufous. Protliorax subquadrate, 

 about one-half wider than long, slightly wider at base than apex, distinctly 

 punctate at base and apex ; apex eniarginate, the anterior angles rounded, mod- 

 erately prominent; base feebly eraarginate ; transverse impressions obsolete; 

 median line entire; basal inii)ressioiis broad, deep, bifoveate, the foveiu punctate; 

 sides with the margin narrowly reflexed, arcuate, sinuate in front of the hind 

 angles, which are rectangular and acutely carinate. Elytra convex, scarcely 

 flattened on tlie disk, together scarcely wider than the thorax and less than 

 twice as long as wide, striate; strite distinctly punctate, more finely toward the 

 apex, the scutellar stria moderately long, the eighth with the row of ocellate 



