THE DIPTEKOUS GENUS DOLICHOPUS IN NORTH AMEEICA. 143 



femora each with one preapical bristle; the former also has a smaller 

 bristle on the posterior side close to the tip; hind femora nearly- 

 glabrous below. Posterior tibiae only slightly thicker than the 

 others, their tips black for one-fifth their length, this black being 

 poorly defined. All tarsi one and a fourth times as long as their 

 tibiae; fore tarsi yellow with the last two joints black, still the base 

 of the fourth is yellowish; first joint as long as the three following 

 joints taken together; middle tarsi black from the tip of the first 

 joint; hind tarsi wholly black. Calypters and halteres yellow, the 

 former with black cilia, which however have a yellowish color when 

 viewed in certain directions. 



Wings (fig. 95) grayish; costa not enlarged at tip of fifth vem; last 

 section of fourth vein a little bent before its middle; hind margin of 

 wing scarcely indented at tip of fourth vein, rather evenly rounded, 

 the anal angle being only moderately developed. 



Described from 1 male taken at Springfield, Massachusetts, by 

 G. Dimmock. 



Type.— Male, Cat. No. 23023, U.S.N.M. 



No. 96. DOLICHOPUS DEFECTUS, new species. 



3Iale. — Length, 4 mm.; of wing, 3.5 mm. Face rather wide for a 

 male, silvery white. Front dark shining green. Antennae (fig. 96a) 

 black; first joint yellowish below, still sometimes the first joint is 

 almost wholly black; third joint rather large, a little longer than 

 wide, somewhat oval in outline, scarcely pointed at tip. I>ateral 

 and inferior orbital cilia pale, a few of the upper cilia black. 



Thorax dark green or blue-green, shining; pleurae dulled with 

 white pollen. Abdomen green, sometime with coppery reflections, 

 its incisures black; the white pollen on its sides not very conspicuous. 

 Hypopygium black; its lamellae moderately large, somewhat oval 

 or more quadrilateral in outline, being rather truncate at tip and 

 abruptly narrowed into the stem, white with narrow black border 

 on apical and upper margins, jagged and bristly on outer end, 

 fringed with blackish hairs above. 



Fore coxae yellow with a small blackish spot on outer surface 

 near the base, their anterior surface nearly bare, still with a few 

 minute black hairs, especially along the inner side. Middle and 

 hind coxae black with yellow tips. Femora and tibiae yellow. 

 Middle and hind femora each \vith one preapical bristle, the latter 

 nearly bare below, but with a row of very delicate short hairs on 

 lower inner edge; posterior tibiae black at tip for about one-fifth 

 their length, the glabrous stripe on upper surface can be seen as 

 a shining line between the rows of large bristles, inside of the inner 

 row of bristles is another glabrous line extending nearly the whole 

 length of the tibia. Fore and middle tarsi about one and a fourth 



