THE DIPTEROUS GENUS DOLICHOPUS IN NORTH AMERICA. 169 



Described from 2 males and 1 female taken at Nain, Labrador, 

 August 18. 



The formation of the fore tarsi and the costal enlargement are very- 

 much like that of splendidus Loew. 



Type and allotype. — ^In the collection of the Boston Society of 

 Natural History. 



No. 117. DOLICHOPUS PORPHYROPS, new species. 



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

 wide, silvery white, but slightly tinged with yellow. Front violet 

 with a narrow edge of green in front and along the orbits. Antennae 

 (fig. 117a) black; first joint with the lower half yellow; third joint 

 large, nearly three times as long as wide, pointed at tip, arista in- 

 serted near apical third, longer than the antennae. Lateral and 

 inferior orbital cilia whitish; about six of the upper cUia on each 

 side black. 



Thorax green, with three bright coppery vittae on the dorsum, 

 the median one sharply defined, the lateral ones just above the 

 pleural suture, wide and not so distinctly limited, extending from 

 the front to the root of the wing; anterior portion of the dorsum 

 somewhat dulled with brownish gray pollen; pleurae with silvery 

 white pollen. Abdomen green with coppery reflections, which are 

 more conspicuous on the hind margins of the -segments; the white 

 pollen on its sides abundant. Hypopygium black; its lamellae (fig. 

 117&) rather large, somewhat quadrilateral in outline, a little longer 

 than wide, white, with a black border, which is wide on apical, narrow 

 on upper margin, jagged and bristly at apex, fringed above with 

 dark, below with pale hairs. 



Fore coxae yellow, iimerhalf of front surface with little black hairs, 

 inner half with minute pale ones. Middle coxae black on the outer 

 surface, with yellow tips. Hind coxae almost wholly yellow. Fe- 

 mora and tibiae yellow. Middle and hind femora each with one 

 preapical bristle, the latter nearly glabrous below. Posterior tibiae 

 very little thicker than the others^ blackened at tip, but the black 

 shading into the yellow. Fore tarsi (nearly like fig. 116a) about one 

 and a half times as long as their tibiae; first four joints yellow, fifth 

 black; first three joints slender, fourth short, somewhat triangulai', 

 not much longer than the width of apical end; fifth joint much com- 

 pressed and widened, somewhat triangular, nearly as wide at apex 

 as long, truncate at tip, about three times as long as the fourth joint 

 and about equal to the third in length. Middle tarsi longer than 

 their tibiae, black from the tip of the first .joint, which has a large 

 bristle at apical fourth on upper surface. Hind tarsi wholly black. 

 'Calypters and halteres yellow, the former with black cilia. 



