154 BULLETIi^ 116, UIsITED STATES ^^ATIOXAL MUSEUM. 



Wings (fig. 105) uniformly tinged with brownish gray; costa a httle 

 thickened just before the tip of first vein and tapering to its tip, 

 still this enlargment is a little more conspicuous just at the tip of 

 first vein; last section of fourth vein rather sharply bent at its 

 middle and ending a little before the apex of the wing; third vein 

 bent backward toward its tip, still the tips of third and fourth vein 

 widely separated; hind margin of wing indented at tip of fifth vein, 

 rather evenly rounded, the anal angle being but little developed. 



Female. — Face wide with coarse white, almost silvery pollen; 

 fore coxae sometimes wholly yellow; hind coxae largely yellow, 

 sometimes almost wholly so; middle tibiae and tarsi as in the male; 

 wings as in the male. 



Described from 1 male and 3 females. The male was taken at 

 Algonquin, Illinois (Nason) ; 2 females were taken at Battle Creek, 

 Michigan (Aldrich) ; 1 female at Buffalo, New York, June 10, 1908 

 (Van Duzee) . 



Type.— Male, Cat. No. 23027, U.S.N.M. 



The male and female of this species can easily be separated from 

 those of setosus Loew by the three bristles on the lower surface of 

 the middle tibiae and the large bristle on upper edge of the middle 

 basitarsi; in setosus there is only one bristle on the lower edge of the 

 middle tibiae and no bristle at all on the middle basitarsi. This last 

 character is the most constant one. 



No. 106. DOLICHOPUS SETOSUS Loew. 



Dolichopus setosus Loew, Cent., vol. 2, 18G3, p. G3; Mon. N. Amer. Dipt., pt. 2, 

 1864, p. 73. 



Male. — Length 4.5-5 mm. ; of wing the same. Face rather narrow, 

 narrowest below, silvery white. Front blue or violet, shining. 

 Antennae black; first joint yellow below; third joint rather large, 

 longer than wide, somewhat conical in outline, a little pointed at tip. 

 Lateral and inferior orbital cilia yellowish white, about six of the 

 upper cilia on each side black. 



Thorax green, sometimes almost violet; dorsum with a little gray 

 pollen on its anterior portion, which sometimes has bronze reflections ; 

 pleurae with a little gray pollen. Abdomen green with bronze and 

 sometimes blue reflections; the white pollen on its sides abundant. 

 Hypopygium black; its lamellae (fig. 106a) moderately large, some- 

 what triangular in outline with the upper apical corner rounded, 

 whitish with a black apical border, jagged and bristly at lower apical 

 corner, otherwise the apical margin is fringed with long blackish 

 hairs. 



Fore coxae yellow with a small brownish spot at base on outer side, 

 anterior surface with white pollen, its inner half with black hairs, on 

 outer half the hairs are mostly yellow. Middle and hind coxae 



