148 DIPTERA OF NORTH AMERICA. 



antenna?, the smaller number of facial bristles and their different 

 position, finally, by its hardly whitish wings. Cinereous, opaque. 

 Front rather broad, a little darker than the remainder of the body, 

 with an impressed longitudinal line on each side ; frontal lunule 

 very narrow, whitish pollinose. Antenna? black, a whitish polli- 

 nose dot on the upper edge of the second joint, bristle pectinated 

 with four or five long hairs. Face moderately broad, gibbous, its 

 upper half distinctly keeled, the lower one convex, receding at the 

 aperture of the mouth. Two bristles on each side of the face, 

 approximated to the eyes. The very narrow orbit of the eyes 

 becomes broader on their under side. Cheeks broader than in 

 most Discocerince. The cinereous color merges into yellowish on 

 .the thorax ; on the upper side of the abdomen, especially towards 

 the apex, it becomes more distinctly hoary. Feet concolorous to 

 the rest of the body, hoary with a whitish pollen ; anterior tarsi 

 yellowish, blackish towards the tip; hind tarsi entirely obscure. 

 Halteres white. Wings hyaline, slightly tinged with an impure 

 whitish, costal vein not incrassated. 

 Hub. Maryland. (Osten-Sacken.) 



5. I>. leiicoprocta LOEW. 9 (Translated from Berl. Entom. Zeitschr. 

 1861, p. 355, by R. Osten-Sackeii.) Cinerea, abdominis atri segmento 

 ultimo niveo, alls hyalinis. 



Cinereous, abdomen black, its last segment snow white, wings hyaline. 

 Long. corp. 0.064. Long. al. 0.07. 



Front brownish-cinereous, opaque. Antenna? rufous, third joint 

 fuscous, bristle pectinated with five or six long hairs. Face yel- 

 lowish-white, its upper half keeled, the lower one convex, furnished 

 on each side with three strong bristles. The narrow cheeks, as well 

 as the whole orbit of the eyes, are whitish. Upper side of the 

 thorax blackish-cinereous, opaque, with short black hairs. Pleura? 

 whitish pollinose. Scutelluna^concolorous with the thorax. Ab- 

 domen black, opaque, last segment rather short, shining white. 

 Fore coxa? black, with a white reflection, yellowish at the tip; 

 trochanters yellow ; femora black, cinerascent with a whitish pollen, 

 tip yellow ; fore and hind tibia? black, yellow at basis and apex ; 

 the intermediate ones entirely flavescent ; all with a whitish re- 

 flection on the upper side; tarsi yellow, last joint blackish. Wings 

 hyaline, the third segment of the costa is equal to two-thirds of 

 the length of the second. 



Hob. Maryland. (Osten-Sacken.) 



