THE DIPTEROUS GENUS DOLICHOPUS IN NORTH AMERICA. 155 



black with yellow tips, femora and tibiae yellow. Middle and hind 

 femora each with one preapical bristle, the latter ciliated below with 

 long delicate hairs for their entire length, those on basal third rather 

 short; the longest of the hairs are nearly twice as long as the width 

 of the femora and a little wavy at tip. Posterior tibiae black at 

 tip for one-sixth their length, a little thickened; the glabrous stripe 

 on upper edge quite distinct but not reaching the tip; most of the 

 inner surface is glabrous, but this narrows apically. Fore tarsi 

 about one and a fourth times as long as their tibiae, black from the 

 tip of the first joint, which is about as long as the three following 

 joints taken together, all the joints of regularly decreasing length. 

 Middle tarsi a little longer than their tibiae, black from the tip of the 

 first joint, their basitarsi without a bristle above. Middle tibiae 

 with one long bristle below. Hind tarsi wholly black. Calypters 

 and halteres yellow, the former with black cilia. 



Wings (fig. 106) grayish; costa with a small knotlike enlargement 

 at tip of first vein; last section of fourth vein bent two-fifths its 

 length from its base, from which point it is very nearly parallel with 

 fourth; hind margin of wing a little indented at tip of fifth vein, 

 rather evenly rounded, the anal angle not being very prominent. 



Female, — Face wide, silvery gray; third antennal joint about as 

 wide as long, nearly round in outline, but pointed at tip; fore tarsi 

 black from the tip of the first joint, still the base of the second is a 

 very little yellow; wings as in the male, except that there is no en- 

 largement of the costa at tip of first vein; middle tibiae with one 

 long bristle below, their basitarsi without a bristle. 



Kedescribed from the single type specimen, which is from Massa- 

 chusetts; 1 male from the Osten Sacken collection, taken at New 

 York; 1 male taken at East Aurora, New York, June 11, 1911; 1 

 male from Woods Hole, Massachusetts; 1 male taken at New Bed- 

 ford, Massachusetts; and 1 female taken at Kidgeway, Ontario, June 

 6, 1909. 



The female on the same pin as the type is not the same species, 

 one female standing with these marked "setosws?" is the female of 

 flageUitenens Wheeler; another female standing with the Osten 

 Sacken male may be this species but has no head. 



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

 chusetts. 



No. 107. DOLICHOPUS SERRATUS, new species. 



Male. — Length 5.2 mm. ; of wing 5 mm. Face rather wide, nar- 

 rower on lower half, silvery white. Front shining green. Antennae 

 black; first joint yellow below, especially at apex; third joint oval, 

 a little longer than wide, rather rounded at tip. Lateral and inferior 

 orbital cilia whitish, about six of the upper cilia black. 



