40 BULLETIN 116, UNITED STATES NATIONAL MUSEUM. 



without a bristle above. Calypters and halteres yellow, the former 

 with black cilia. 



Wings nearly hyaline; costa with a small knotlike enlargement 

 at tip of first vein; hind margin of wing scarcely indented at tip of 

 fifth vein; anal angle prominent. 



Redescribed from the single typo specimen in the American Mu- 

 seum in New York, taken at Chicago, Ilhnois, Ma}' 8, 1896. 



No. 2. DOLICHOPUS MONTICOLA, new species. 



Male. — Length, 4 mm. ; of wing, 3.5 mm. Face of moderate width,, 

 ocher yellow above, becoming white below. Front green, shining. 

 Antennae (fig. 2a) wholly black; third joint about as long as wide, 

 somewhat orbicular in outline, still pointed at tip, proboscis and 

 palpi black, orbital cilia wholly black. 



Thorax green with blue or sometimes bronze reflections, a little 

 dulled with brownish pollen, which is almost invisible when viewed 

 from above; pleurae more black with gray pollen. Abdomen green 

 with slight bronze reflections and narrow black incisures ; the white 

 pollen on its sides rather abundant. Hypopygium black, its lamellae 

 of moderate size, somewhat triangular in outline, but rounded apically, 

 whitish with broad black border, fringed with fine brown hairs on 

 apical portion, a little jagged at lower corner. 



Coxae, legs, and feet wholly black, the articulations of the femora 

 and tibiae narrowly brownish yellow. Fore coxae covered with white 

 pollen and little black hau-s on their anterior surface. Middle and 

 hind femora each with one preapical bristle, the latter not ciliate, 

 but with very minute, delicate brown hairs on lower inner edge. 

 Hind tibiae gradually thickened apically; the glabrous stripe on 

 upper edge may be seen for nearly their whole length as a narrow 

 shining line between the two rows of large bristles. Fore tarsi plain, 

 not longer than their tibiae; the basitarsi nearly as long as the 

 remaining four joints taken together; fourth joint slightly shorter 

 than fifth, which is about as long as the third; middle and hind tarsi 

 each a little longer than their tibiae. Calypters and halteres yellow, 

 the former with black cilia. 



Wings (fig, 2) dark grayish, strongly tinged with brown in front of 

 third vein, sometimes back to the fifth, except beyond the cross 

 vein, where it is grayish; cross vein slightly bordered with brown; 

 costa not enlarged at tip of first vein; last section of fourth vein bent 

 just before its middle; hind margin of wing not indented at tip of 

 fifth vein, evenly rounded, the anal angle being nearly obsolete. 



Female. — Face broad, about half as wide as long; wings darker 

 than in the male; otherwise about as in the male. 



Described from 11 males and 9 females, taken on Mount Constitu- 

 tion, Washington, July 7-17, by J. M. Aldrich; and 1 male taken at 



