NORTH AMKRICAN LEPIDOPTERA. 173 



The first group contains insects at once recognizable by tlie dis- 

 colored disc of thorax. They agree also in narrower, pointed wings, 

 in very heavily spinose fore and middle tibia, and, with one exception, 

 no special armature of the fore tarsi. The spurs of the middle and 

 hind tibi?e are short. 



Kahnice is easily distinguished from all the other species by its 

 yellowish brown color. All the others have a shade of gray as base. 



Drnpiferanan has the costal region much paler than the rest of 

 the wing, which is a dull fuscous gray, with a decided brownish tint. 

 A variety has been named utahensis, and another vancouverensls, by 

 Mr. Hy. Edwards. In this species, while there is no distinct arma- 

 ture of fore tarsi, the series of spines outwardly show some unusually 

 long and prominent ones indicating the more distinct armature of 

 the other groups. 



Perelegam is a much more evenly colored species, with very dark 

 gray ground, and a submarginal whitish band. The palpi are much 

 more distinct than in either of the preceding species. The armature 

 is like drupijerarum. 



Gordius is, in wing shape, much like the preceding, but the palpi 

 are smaller; there is a luteous shade over the primaries which show 

 also a usually very distinct white discal spot, while the median band 

 of the secondaries is somewhat fainter than usual. The armature of 

 legs is as in kahnke. 



Luscitiosa is closely allied, but is still more brown, the discal white 

 spot is wanting on primaries, the secondaries are yellow, the median 

 band reduced to a mere trace and often entirely wanting. The palpi 

 also are still shorter, and the outer margin of ])rimaries is more 

 evenly oblique, not so convex as in gordius, w'hich it resembles in 

 armature of legs. 



Albescens differs from all in this group by the heavily armed fore 

 tarsi, there being three stout outer spines to the first joint and two 

 to the second. The middle tibia3 are not so heavily spined and the 

 spurs are moderate. In maculation also it differs from all the others 

 by the oblique, submarginal black streak followed by a whitish shade. 

 It combines the features of the i)resent with those of the following 

 group. 



This following group is characterized l)y concolorous dorsum of 

 thorax, the i)atagi:e black margined, wings rather wider, arn)ature 

 of fore tarsi usually distinct. 



