THE DIPTEROUS GENUS DOLICHOPUS IN NORTH AMERICA. 53 

 No. 16. DOLICHOPUS ADAEQUATUS, new species. 



Male. — Length 4 mm.; of wing the same. Face wide, covered with 

 dark brown pollen, which is coarse and somewhat yellow in some 

 individuals. Front shining green. Antennae (fig. 166) wholly 

 black; third joint slightly longer than wide, oval, romided at tip. 

 Lower orbital cilia whitish; the black cilia descend about one-third 

 of the eye height. 



Thorax green, not very dark or bright, but shining and with blue 

 or bronze reflections; pleurae dulled with white pollen. Abdomen 

 shining green with coppery reflections, especially toward its apex, 

 sometimes with blue reflections on the basal segments. Hypopygium 

 black; its lamellae (fig. 16a) moderately large, somewhat triangular, 

 white with rather wide black border on the rounded apical margin, 

 which is jagged and bristly, their upper and lower edges fringed 

 with delicate brown hairs. 



Coxae, legs and feet wholly black. Fore coxae with conspicuous 

 little black hairs and white pollen on the anterior surface. Middle 

 and hind femora each with two preapical bristles, placed one before 

 the other, the latter ciliated with brown hairs on lower inner edge of 

 their center, the longest of these hairs about three-fourths as long as 

 width of femora. Hind tibiae thickened, upper side with the bristles 

 in the usual two rows large, about six in each row, the glabrous 

 stripe between them distinct and widely extending upon the inner 

 side of tibia on its basal half, lower side with a row of bristlelike 

 hairs of somewhat unequal length and ending in one large bristle 

 a little distance before the tip. Fore tarsi about one and a fourth 

 times as long as their tibiae, the first joint a little longer than the two 

 succeeding joints taken together, fourth joint slightly shorter than 

 the fifth. Middle tarsi one and a fourth, hind tarsi one and a third 

 times as long as their tibiae. Calypters and halteres yellow, the 

 former with black cilia. 



Wings (fig. 16) grayish; costa not or scarcely enlarged at tip of 

 first vein; last section of fourth vein a little bent at its middle; hind 

 margin of wing a little indented at tip of fifth vein, evenly rounded, 

 the anal angle being very little developed. 



Female. — Face a little wider than in the male; hind femora not 

 ciliate but with delicate little brown hairs on inner edge of apical 

 half; hind tibiae not or scarcely thickened; front of wing a little 

 brownish as far back as the third vein; otherwise about as in the 

 male. The middle tibiae have one bristle below and their basitarsi 

 are without a bristle above. 



Described from 22 males and 9 females. J. M. Aldrich took 6 in 

 Idaho, June 12-20; Baker took 1 in Colorado; I took 23 at Wells, 

 Nevada, June 6, and 1 at Victor, Colorado, June 11, at 9,900 feet 



