6 PROCEEDINGS U. S. NATIONAL MUSEUM tout* 



above on facial ridges, which are decidedly prominent and sharp; 

 ocellars proclinate and (divaricate, outer verticals minute. Palpi 

 yellow, of ordinary size; i^roboscis small. Cheek and back of head 

 with only black hairs. Thorax with yellowish pollen, black in 

 ground color, but with a reddish tinge on the apical part of scutel- 

 lum. Mesonotum with a pair of blackish stripes and a distinct tri- 

 angular black spot in front of inner presutural; also an elongated 

 spot behind the suture. Chaetotaxy : Acrostichal 3, 3 ; dorsocentral 

 2, 4; humeral 3; posthumeral 2; presutural 2 (inner two-thirds as 

 long as outer); notopleural 2; supraalar 3; intralar 3: postalar 2; 

 sternopleural 2, 1; scutellum with three lateral, one discal, and a 

 smallish divergent apical pair; postscutellum well developed; pos- 

 terior calypter yellowish white. 



Abdomen with yellowish-gray pollen on last three segments, more 

 dense on the fourth, on the two preceding becoming thinner pos- 

 terixDrly so as to show a black but not very shining ground color. 

 Second segment with a pair of median marginal,s; third segment 

 with or without distinct pair of discals and a marginal row of eight : 

 fourth segment with a discal row of six, and a few apical. 



Legs black; middle tibia with one bristle on outer front side, hind 

 with a sparse row rather uniform, except one larger below middle. 



Wing subhyaline. rather rounded in outline, bend of fourth vein 

 with gradual curve, the first posterior cell open, or barely closed just 

 before tip. Hind cross vein rather straight and erect, somewhat 

 nearer to bend than to .small cross vein; first vein bare, third with 

 two or three bristles at base. Last section of fifth vein hardly one- 

 third the preceding; costal segment beyond tip of second vein con- 

 siderably more than half as long as the one before it. 



Male. — Head somewhat shriveled ; third antennal joint longer and 

 wider than in female, black almost to base; it as wide as the para- 

 facial; orbital bristles present as in the female. Genitalia quite 

 ^mall, black, the inner forceps distinctly separated, short, rather 

 broad at tip; outer forceps with broad black base attached to seg- 

 ment, the free part abruptly tape/ing and slender, black with slightly 

 rounded tips. 



Length, 4-6 mm. 



Described from four females and one male, received from Dr. J. L. 

 King; they were reared from PopUlia japonlca Newman at Riverton, 

 N. J., from material obtained in Japan; emerged July 24, 1925. 



Type.—FQnvAlQ, Cat. Xo. 41452, U.S.N.M. 



