THE DIPTEROUS GENUS DOLICHOPUS IN NORTH AMERICA. 141 



theii' joints of regularly decreasing length; middle tarsi black from 

 the tip of the first joint. Hind tarsi wholly black. X^alypters and 

 halteres yellow, the former with black cilia, still appearing yellow in 

 certain lights. 



Wings (fig. 93) grayish; costa not distinctly enlarged at tip of 

 first vein, tapering to its tip; last section of fourth vein a little bent 

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

 anal angle not prominent. 



Described from 2 males; 1 taken by me at East Aurora, New York, 

 June 9, 1918; the other at Lynden, Vermont, June 13, 1914, by A. L. 

 Melander. 



Type.— Male, Cat. No. 23021 , U.S.N.M., from East Aurora, New York . 



This differs from canadensis in having t^e lamellae smaller and 

 more regularly oval, the fore tarsi almost wholly yellow, and with 

 the fifth joint shorter than the fourth; while in canadensis the fifth 

 joint is a little longer than the fourth and the last two and a half 

 joints are black. 



No. 94. DOLICHOPUS CANADENSIS, new species. 



Male. — Length, 4.75 mm.; of wing, 3.75 mm. Face moderately 

 wide, silvery white. Front shining green with bronze reflections in 

 the center. Antennae (fig. 94) black, first joint yellow below; third 

 joint one and a half times as long as wide, oval, still obtusely pointed 

 at tip. Palpi yellow. Lateral and inferior orbital cilia white, about 

 seven of the upper cilia on each side black. 



Thorax shining green with a little white pollen on the anterior 

 portion of the dorsum, which has a rather broad, median, shining 

 vitta; this vitta and a spot on each side at the transverse suture are 

 more or less bronze colored; pleurae dulled with white pollen. Abdo- 

 men shining green with slight bronze reflections, which are more 

 conspicuous on the apical segments, and white pollen on the lower 

 part of its sides. Hypopygium black; its lamellae large, nearly twice 

 as long as wide, rounded at apex, gradually tapering into the stem; 

 white with a black border on the apical margin, the lower corner of 

 which is jagged and bristly, fringed above with delicate brown hairs. 



Fore coxae wholly yellow with silvery pollen and minute yellow 

 hairs on the anterior surface, a few minute black hairs on their 

 inner edge. Middle and hind coxae black with yellow tips. Femora 

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

 bristle, the latter nearly glabrous below on inner side. Posterior tibiae 

 scarcely thicker than the others, a little infuscated at tip, especially 

 on inner surface, where they are quite black for a short distance. All 

 tarsi about one and a fourth times as long as their tibiae ; anterior 

 pair (fig. 94a) yellow, blackened from the middle of the third joint, 

 fifth almost imperceptibly compressed, longer than fourth joint, 

 187329—21 10 



