282 BULLETIN 116, UNITED STATES NATIONAL MUSEUM. 



No. 207. DOLICHOPUS TENUIPES Aldrich. 



Dolichopus Aldrich, American Naturalist, 1894, p. 35 (describes courtship). 

 Dolichopus tenuipes Aldrich, Kans. Univ. Quart., vol. 2, 1894, p. 155. — Me- 

 LANDER and Brues, Biol. Bull., vol. 1, 1900, p. 148. 



Male. — ^Length 5-5.5 mm.; of wing 4-5 mm. Face wide, a little 

 narrowed below, silvery white. Front green, dulled with grayish 

 white pollen. Antennae j'ellow, third joint blackish with the base 

 yellow, about as long as wide, pointed at tip. Lateral and inferior 

 orbital cilia white, about four of the upper cilia on each side black. 



Thorax green with bronze reflections; dorsum covered with thick 

 brownish gray or yellowish pollen; pleurae dulled with white pollen. 

 Abdomen green with more or less bronze reflections ; the white pollen 

 on its sides abundant and extending upon the dorsum. Hypopy- 

 gium black; its lamellae rather large, elliptical, but rather pointed at 

 tip, white with a narrow brown border on the apical margm, fringed 

 with little brown hau^s on the apical edge and with pale hairs above 

 and below. 



Coxae, femora and tibiae yellow; middle and hmd coxae more or 

 less blackened on outer siu^face. Fore coxae with silvery pollen 

 and minute yellow hairs on anterior surface, a few black hairs 

 along the inner edge. Middle and hmd femora each with one pre- 

 apical bristle, the latter without cilia below. Middle tibiae with one 

 bristle below, their basitarsi without a bristle above. Posterior 

 tibiae thickened, their imier surface with a short glabrous spot, v/hich 

 does not reach the base and occupies about one-fourth their length. 

 Fore tarsi (fig. 207a) twice as long as their tibiae; second joint one 

 and a fourth times as long as the first, second and thu'd very thin, 

 glabrous on their sides, brownish, third about equal to the first m 

 length; fourth joint scarcely wider than the third and very short 

 about as long as wide, with two long hahs above; fifth jomt very thin, 

 black, compressed, oval, extending far beyond the claws which are 

 placed near its basal third, frmged toward the tip with a few mmute 

 black hairs, about two-thkds as long as third joint. Middle tarsi one 

 and one-fourth times as long as their tibiae, brownish almost from the 

 base, but scarcely black even at tip. Hind tarsi blackish from the 

 tip of the first joint, which is dark yellow. Calypters and halteres 

 yellow, the former with black cilia. 



Wings (fig. 207) grayish; costa black, without distmct enlargement 

 at tip of first vein, although somewhat thicker at that point and 

 tapermg to its tip; last section of fourth vem bent just beyond its 

 basal third; third vein bent backward at its tip; hind margin of whig 

 only a little hidented at tip of fifth vein, rather evenly rounded, the 

 anal angle not being j)roniment. 



Female. — Face a little wider than in the male, and more grayish; 

 coxae and wings as in the male; hind tibiae without the glabrous spot 



