378 NEW YORK STATE MUSEUM | 
visible only in certain lights. Pleura also with a whitish re- — 
flection; abdomen with silvery white spots on the second and — 
on the last two segments, wanting in rubbed specimens; the © 
posterior margin of the first segment with long and dense 
brownish cilia. Head black, face grayish white; antennae and © 
palpi brownish black, the former more slender than is usual 
with the members of this genus, with whitish reflections on 
some parts. Legs dark brown; front coxae yellowish, fore 
tibiae silvery white outwardly; middle tibiae yellow at the base, 
hind tibiae likewise, though in less degree, light brown, with a 
whitish reflection; metatarsi of the hind legs yellowish at the 
base; the hairs of the fore and hind femora, and particularly 
on the extensor surface of the hind tibiae, conspicuous. Hal- 
teres bright yellow; wings purely hyaline, with delicate and 
transparent veins, those of the anterior margin being somewhat 
thicker and more conspicuous; the wing surface with a golden 
brown reflection; the media not petiolate. The short, scattered 
hair of the thorax seldom distinct, the color of the legs variable 
in intensity. 
Female. In coloring does not resemble the male iu the least. | 
The ground color is blackish brown; the dorsum of the thorax 
covered with a depressed yellow pile, on the margins with a 
whitish reflection, on the center with a grayish reflection, the 
pleurae grayish white. Abdomen somewhat shining; on the 
sides whitish or yellowish gray; on the venter, at least at the 
base, in living specimens, yellow, which is continued around on — 
the dorsum in some specimens, usually not distinct in dried 
specimens. Legs brown, usually paler than those of the male; 
the tibiae, with the exception of the tip, and the fore coxae whit- 
ish or yellowish white, the tips of the tibiae and the tarsi black, 
the basal half of the hind metatarsi and sometimes also the 
extreme base of the following joint yellowish. Front and face 
———— 
gray; antennae and palpi brown, the former paler at the base. 
In other particulars as with the male. Length 2 to 3mm. 
Translation from Schiner, Fauna Austriaca, 2:365 
According’ to -Schiner [loc. cit.] this is the species whose life 
history has been described by Fries, Westwood and Heeger. 
According to Schiner also, sericea is a synonym of rep- 
tans. Of sericea Westwood writes that the larva pos- 
sesses three unbranched blood gills, and that the pupa oe 
eight thoracic respiratory filaments on each side. 
This European species has been reported by Lundbeck as 
occurring in Greenland. (Diptera groenlandica, 1898) 
— SS SS eee eee 
