220 BULLETIN 116^ UNITED STATES NATIONAL MUSEUM. 



white, the black cilia not quite reaching down to the middle of 

 the eye. 



Thorax green with considerable gray pollen; pleurae dulled with 

 white pollen. Abdomen green with coppery reflections; the white 

 pollen on its sides abundant and extending upon the dorsum; the 

 second segment has a bunch of long yellow hairs on each side, the tips 

 of these hairs reach upon the fourth segment ; the third segment also 

 has a similar bimch of yellow hair, but it is much smaller and shorter. 

 Hypopygium black; its lamellae (fig. 158a) of moderate size, whitish 

 with a narrow black border on apical and upper margins, jagged and 

 bristly at apex, fringed above with delicate white hairs. 



Fore coxae yellow with a black or green streak on the outer posterior 

 edge, inner edge of anterior surface with little black hairs. Middle 

 and hind coxae black with yellow tips. Middle femora with one pre- 

 apical bristle; hind ones with a row of bristles of increasing length, 

 ending in the usual preapical bristle, without cilia below. Posterior 

 tibiae thickened, a little compressed, with a shallow groove on each 

 side, that on the inner side glabrous. Fore and middle tarsi stout, 

 scarcely as long as their tibiae, infuscated from the tip of the first 

 joint, still the joints sometimes a little yellow at base. Hind tarsi 

 black from the tip of the first joint. Calypters, their cilia and the 

 halteres yellow. 



Wings (fig. 158) grayish; costa with an elongated enlargement at 

 tip of first vein; last section of fourth vein rather sharply bent before 

 its middle; hind margin of wing deeply indented at tip of fifth vein 

 with a very slight sinus at tip of sixth vein; anal angle of wing 

 prominent. 



Female. — Face but little wider than that of the male; antennae 

 slightly shorter; thorax, legs, feet, and wings about as in the male, 

 except that the costa is not enlarged at tip of first vein; there are 

 no tufts of yellow hair on the sides of the second and third abdominal 

 segments. 



Redescribed from many males and females. J. M. Aldrich has 

 specimens from Brigham, Utah, July 4, 1911, taken on parsnip 

 flowers; Monterey County, California, July 15 (Wheeler); Santa 

 Clara County, California (Baker); Stanford University, California, 

 Oct. ; Socorro, New Mexico (S. W. Williston) . I took it at Palo Alto, 

 California, June 3; Berkeley, California, Oct. A. L. Melander took 

 it at Stanford, California, June 30; Pullman, Washington, June 30. 

 F. E. Snow took it in Cochise County, Arizona, Aug., at 3,750 feet 

 elevation. 



Tyj)e locality. — San Rafael, Marin County, California. Wheeler 

 reports it from Arizona; Melander and Brues from Wyoming and 

 Arizona. 



Type.— In Museum of Comparative Zoology, Cambridge, Massachu- 

 setts. 



