116 BULLETIN 116, UNITED STATES NATIONAL, MUSEUM. 



darkened above. From facatus, new species, it differs in having 

 black cilia on the caly])ters and the brown on upper edge of fore 

 femora, fucatus has yellow cilia and the fore femora wholly yellow. 

 It differs from sincerus Melander and suhdirectus, new variety, in 

 having the wings brownish in front of third vein, front green and 

 the tips of hind tibiae sharply black; in these other two forms th-e 

 wings are almost hyaline, front violet and the hind tibiae yellowish 

 on inner side almost to the tip, more black on the outer side, but 

 the black shading into the yellow. 



No. 72. DOLICHOPUS DISCOLOR, new species. 



Male. — Length 4.5-5 mm.; of wing 4-4.2 mm. Face rather wide, 

 silvery white. Front shining green with more or less violet reflec- 

 tions. Antennae black; first joint yellow below; third joint but 

 little longer than wide, somewhat conical in outline. Palpi yellow. 

 Lateral and inferior orbital cilia yellowish, a few of the upper cilia 

 black. 



Thorax green, dorsum with grayish brown pollen, which leaves the 

 posterior part and a median vitta shining, often with bronze or blue 

 reflections; pleurae dulled with white pollen. Abdomen green with 

 black incisures and coppery reflections; the white pollen on its sides 

 abundant and extending upon the dorsum. Hypopygium black; 

 its lamellae (fig. 72a) of moderate size, short oval, or somewhat 

 quadrate in outline, being cut off rather abruptly at apex and the 

 upper angle at base rising abruptly from the stem, white with rather 

 broad black border on apical and upper margins, jagged and bristly 

 at apex, fringed above with rather long brown hairs. 



Fore coxae yellow, infuscated at base, sometimes the outer side 

 is black for half their length, sometimes it has only a black spot at 

 base, anterior surface with conspicuous black hairs. Middle and 

 hind coxae black with yellow tips. Femora yellow; middle and 

 hind ones each with one preapical bristle, the latter black at tip 

 on upper edge as far as the preapical bristle, the lower inner edge has 

 a row of minute yellow. hairs, not ciliated. Tibiae yellow, posterior 

 jiair scarcely thickened, black at ti]) for about one-fifth their length, 

 the glabrous stripe on upper surface distinct. Fore and middle tarsi 

 a little longer than their tibiae, black from the tip of the first joint, 

 the former with the first joint as long as the three following joints 

 taken together, fourth and fifth of equal length. Hind tarsi wholly 

 black, one and a third times as long as their tibiae. Calpyters and 

 halteres yellow, the former with black cilia. 



Wings (fig. 72) grayish, strongly tinged with brown in front of 

 third vein; costa not enlarged at tip of first vein; last section of 

 fourth vein bent just beyond its basal third; hind margin of wing 



