98 Journal New York Ent. Soc. [Vol. ii. 



oblique, greatly retreating below, pilose, especially on the sides ; proboscis quite 

 slender, nearly as long as the head, labellre rather slender and as long as the pro- 

 boscis proper; two submarginal and six posterior cells, the usual first posterior cell 

 being divided into two cells by a crossvein situated midway between apex of discal 

 cell and the wing-margin; fourth posterior cell wide open, the anal closed; pulvilli 

 present, empodium bristle-like. (Name from the Greek, i/iefa, between, and 

 p/imgiim, a partition. Type, Xi'stoinyza plaiiiceps Loew. 



Nebritus, gen. nov. 



Head depressed, slightly longer than broad, front nearly horizontal, vertical 

 diameter of eyes scarcely greater than the horizontal, eyes of male separated more 

 than twice as wide as the two posterior ocelli; first joint of antenna: unusually 

 robust, as long as the head, twice as long as the third joint, the latter scarcely as 

 brcud as the second; style wholly wanting; proboscis quite slender, projecting 

 nearly half the length of the head beyond the oral margin, labelhi: rather slender, 

 as Ipng as the proboscis proper; palpi slender, sub-clavate, slightly shorter than the 

 proboscis; face bare, gieatly retreating below; two submarginal and five posterior 

 cells, all of them open, the anal closed; pulvilli present, the empodium bristle-like. 

 (Name from the Greek, nebrilos, like a fawn-skin.). Type, Nchritns pcllucidus, 

 sp. nov. 



Nebritus pellucidus, sp. nov. 



(^\ O — Black, the proboscis, palpi, first antennal joint except the upperside, 

 femora, tibise, base of tarsi, halteres except the extreme apex, and tip of abdomen, 

 yellowish; in the female the middle of the sixth, seventh and eighth abdominal 

 segments at the base are black. Front o.i the upper ihree-fourths sparse black 

 pilose and opaque yellow pollinose, excepting a median Ine and an ocellar spot; 

 lower fourth of front highly polished, sometimes yellowish below, bearing a cluster 

 of black pile at base of each antenna; first antennal joint highly polished, sparsely 

 beset with black pile and bristles, the third joint bearing short biistles at the base; 

 face yellow pollinose except the upper edge, extending as a large spot each side, 

 polished black, a similar spot on each side of the oral margin near its posterior 

 edge; occiput yellow pollinose except in the center, where it is gray, a large polished 

 black spot back of upper corner of each eye. Thorax opaque, somewhat bluish 

 pollinose excepting four nearly equidistant yellow pollinose vittn; which are beset 

 with short yellow and black pile, elsewhere the sparse pile is black. Scutellum mar- 

 ked with two yellow vittre beset with yellow pile; four marginal bristles. Abdomen 

 opaque, lightly yellowish gray pollinose, the short pile on the basal half yellowish, 

 that on the apical half largely black. Wings hyaline, the stigma yellowish. Length. 

 7 to lo mm. 



Southern California. Four males and two females, in April 

 and June. 



Psilucephala and Thereva. — Our si)ecies have been so 

 recently tabulated by the writer (Can. Ent., 1893, pages 197 — 198 

 and 223 — 225) that it is (juite needless to reproduce the tables in 

 this place. In working up the rich material in the National 



