270 BULLETIN 116, UNITED STATES NATIONAL MUSEUM. 



and the inner with six bristles, the usual glabrous stripe between 

 them broad, but a little broken by a few hairs. Fore tarsi (fig. 197a) 

 about one and one-third times as long as their tibiae, infuscated from 

 the tip of the first joint, still the base of the second paler, only the 

 last two joints black; first three joints slender, second and third each 

 two-thirds as long as the joint preceding it, fifth scarcely as long as 

 third; fom-th half as long as fifth, a little widened at tip; fifth com- 

 pressed, a little widened, widest at tip where it is a little less than 

 half as wide as long, fringed above with little black hairs; pulvilli 

 white. Middle tarsi about one and one-fourth times as long as their 

 tibiae, black from the tip of the first joint. Hind tarsi black from 

 the tip of the first joint, sometimes their basitarsi are brown or even 

 black almost to the base. Calypters and halteres yellow, the former 

 with black cilia. 



Wings (fig. 197) grayish, a little darker in front; costa not enlarged 

 at tip of fii'st vein; last section of fourth vein bent before its middle; 

 hind margin of wing a little indented at tip of fifth vein and with a 

 slight sinus nearly opposite the cross-vein; anal angle prominent, the 

 wing being of somewhat equal width. 



F'emale. — Face wider than in the male; fore tarsi plain, about one 

 and one-fourth times as long as their tibiae, colored as in the male; 

 fifth joint about as long as third, fourth a little shorter; bristles of 

 the tibiae about as in the male, except that there are usually three 

 bristles below on middle tibiae; wing about as in the male, except 

 that the hind margin is more evenly rounded, there being no trace 

 of the sinus, and the wing a little wider in the middle. 



Redescribed from 1 type, and many specimens taken in the fol- 

 lowing localities: Moscow, Bellevue, and Grangeville, Idaho, June 

 23-27; Hood River, Oregon, August 9; Indian School, PjTamid Lake, 

 Nevada, July; Mono Lake, California, July 21; Seattle, Washington. 

 All the above were taken by J. M. Aldrich. Thompson took a male 

 at Woodside, California, April 15. C. F. Baker took it in Colorado- 

 A. L. Melander took it in many places in Washmgton, May 15 -Aug- 

 ust 15, and at Kermeos, British Columbia, July 19. 



Tyjje locality. — California. J. M. Aldrich reports it abundant at 

 Moscow, Idaho. Melander and Brues report it from Vancouver 

 Island. 



Type. — In collection of J. M. Aldrich. 



The only difference I can see between the females of coquilletti and 

 talus is that the former has the third vein only slightly bent backward 

 at its tip, while in talus the third vein is distinctly bent back at its 

 tip; this is a poor character to depend on, as it may vary some in 

 both species. 



