198 BULLETIN 116^ UNITED STATES NATIONAL MUSEUM. 



jagged and bristly on lower half of apical edge, fringed above with 

 dark hairs. 



Fore coxae yellow, blackened at base on outer surface for one-third 

 their length, anterior surface with numerous minute black hairs and 

 some delicate pale hairs on upper outer corner; middle and. hind coxae 

 black with yellow tips, sometimes narrowly yellowish at base. 

 Femora and tibiae yellow. Middle and hind femora each with one 

 preapical bristle, the latter ciliated on lower inner edge for about 

 one-fourth their length with dense yellow hairs, which are as long as 

 the width of the femora and leave the basal half and apical fourth 

 bare. Posterior tibiae thickened, a little compressed, lower edge 

 with a row of bristles of uneven length, the longest being as long as 

 those on upper edge; the glabrous stripe on upper surface narrow 

 and not conspicuous, but with a broad glabrous space on the lower 

 part of the basal half of the inner surface, their tips not at all infus- 

 cated. Middle tibiae with three bristles below, one pair at apical 

 third and one bristle at basal third, sometimes with one more bristle 

 near the middle. Fore tarsi (fig. 140a) twice as long as their tibiae, 

 the first joint nearly as long as the tibia and a little longer than the 

 three succeeding joints together; first four joints yellow, fourth more 

 than half as long as third and slightly widened at tip; fifth as long 

 or slightly longer than fourth, black, compressed, widest near the 

 apex, where it is slightly more than half as wide as long, somewhat 

 triangular; the sides of this joint have a slight yellowish or reddish 

 luster in certain lights. Middle tarsi nearly one and a half times as 

 long as their tibiae, the first two joints being nearly as long as the 

 tibia, black from the tip of the first joint, still the base of second a 

 little yellowish; middle basitarsi with a large bristle on upper side. 

 Hind tarsi black, sometimes yellowish on basal portion of first joint. 

 Calypters, their cilia, and the hal teres yellow; sometimes there are 

 a few black hairs among the cilia. 



Wings (fig. 140) grayish, veins yellowish; costa with a slight 

 elongated enlargement at tip of first vein; last section of fourth vein 

 bent at basal third; hind margin of wing a little indented at tip of 

 fifth vein, a little widened between the tips of the fifth and sixth 

 veins; anal angle prominent. 



Described from 2 males from Colorado. 



Type—Male, Cat. No. 23036, U.S.N.M. 



This species differs from siibciliatus Loew in having the cilia of 

 the hind femora confined to about one-fourth of the lower edge, 

 while in that species it extends nearly the whole length of the femora; 

 it also differs in other respects a little. 



