200 MEMOIRS ON THE COLEOPTERA 



with earthy matter; head moderately impressed and punctured, the 

 pale hairs stout; prothorax fully two-thirds wider than long, nearly as 

 wide as the elytra (cf ) to decidedly narrower ( 9 ), rather wider at the 

 middle than at the basal angles, the latter acute and posteriorly 

 prominent but scarcely at all everted, the sides rather strongly, evenly 

 arcuate, more converging anteriorly to the acute and seldom very 

 evidently blunted apical angles, the apex three-fifths as wide as the 

 base, less deeply sinuate than in immunda; surface similar but be- 

 coming coarsely punctato-rugose medially in the female, though not 

 in the male; elytra short, barely two-fifths longer than wide, the 

 parallel sides more strongly arcuate than in the preceding species, 

 rounding inward posteriorly behind the middle, the apical lobe 

 moderately differentiated; surface rather less flat, each with about 

 four close-set irregularly sinuous unduliform and feebly tumid lines, 

 the side margins reflexed throughout, strongly toward base but not 

 much thickened; abdomen more shining than in immunda, punctate 

 apically; legs rather more slender. Length (cf , 9 ) 15.0-16.0 mm.; 

 width 7.7-8.5 mm. New Mexico (Magdalena Mts.), Snow. 



ccenosa n. sp. 



It is highly probable that nitidula and tensa are related to man- 

 cipata, in spite of the very different type of elytral sculpture in- 

 ferable from the original description of the latter species, and, as 

 nitidula is certainly a member of the opaca group, very evidently 

 connected with the more normal species through tensa, it follows, 

 if this surmise is correct, that mancipata is also a member of the 

 opaca group and that a special group for that species is unnecessary. 

 The finely and sparsely punctate head and three irregular elytral 

 ridges, united transversely by anastomosing reticulation, stated of 

 mancipata, coupled with the broader elytral base, would indicate 

 that it cannot be a modification of nitidula, but as in tensa the head 

 is finely and sparsely punctate and the elytra may be conceived to 

 have each three broad and feebly elevated lines, it is supposable 

 that mancipata may be related more closely to tensa than to ni- 

 tidula; but tensa has the elytra no wider at base than the prothorax 

 and the elytral ridges are separated by feeble irregular and equally 

 wide depressed lines, or rather depressions caused by the more 

 lineiform arrangement of the very irregular indentations and in 

 no way united by reticulation. Grant Co., New Mexico, the local- 

 ity of mancipata, lies in the extreme southwestern angle of the ter- 

 ritory, about 200 miles south of Fort Wingate, McKinley Co. 

 The Kansas specimens of opaca are obviously flatter in the elytra 

 than the Colorado specimens and may be subspecifically different. 



