D1SC0CERINA. 147 



isb-black, opaque, almost pure black and sbiniog towards tbe end; 

 first segment not strikingly shortened. Femora and tibia? black ; 

 knees, tibia? at their tips and tarsi yellowish. Halteres white. 

 "Wings grayish-hyaline, with blackish-brown veins; the second seg- 

 ment of the costal vein is at least half as long again as the third. 

 Hub. Washington. (Osten-Sacken.) 



3. D. orbitalis Loew. % . (Translated from Berl. Entom. Zeitschr. 

 1861, p. 354, by R. Osten-Sacken.) — Cinerea, opaca, colore thoracis magis 

 in ochraceum, abdominis in nigrum vergente, antennis runs, oculorum 

 orbita Candida, alis byalinis, segmento costali secundo tertii longitudi- 

 nem modice superante. 



Cinereous, opaque, color of tbe thorax merging in ocbraceous, that of tbe 

 abdomen in black, antennae rufous, orbit of the eyes shining white, 

 wings hyaline, second costal segment a little longer than the third. 

 Long. corp. 0.065. Long. al. 0.07. 



Head obscure cinereous, opaque, orbit of the eyes rather broad, 

 not dilated below the eyes, shining white. Face rather broad, the 

 upper half distinctly keeled, the lower half convex, about six small 

 bristles each side, which are more distant from the orbita? than is 

 generally the case in this genus. Cheeks moderately narrow. 

 Antennae rufescent, third joint rather obscure. On the upper side 

 of the thorax and on the scutel the cinereous color merges in 

 ochraceous ; pleura? somewhat hoary. Abdomen darker than the 

 rest of the body, black towards the apex, very slightly glossy. 

 Femora black, hoary, with a whitish pollen ; tibia? and tarsi yel- 

 lowish, the former with a broad brown ring, the latter with the tip 

 brown. Halteres white. Wings pure hyaline; second segment of 

 the costa a little longer than the third. 



Hub. Washington. (Osten-Sacken.) 



4. D. simplex Loew. (Translated from Berl. Entom. Zeitschr., p. 

 355, by R. Osten-Sacken.) — Cinerea, opaca, antennis nigris, setis faciei 

 utrinque duabus, genis latioribus, tarsis fiavescentibus, apicem versus 

 nigris, alis byalinis. 



Cinereous, opaque, antennae black, two bristles each side of the face, 

 cheeks rather broad, tarsi flavescent, black towards tbe apex, wings 

 hyaline. Long. corp. 0.07. Long. al. 0.09. 



Yery like D. lacieipcnnis, but easily distinguished by its black 



