66 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 63. 



segment with a row of eight; fourth segment on apical half with 

 less numerous bristly hairs than usual in this group. Genital seg- 

 ments entirely black; the united forceps forming a sharp regularly 

 tapering organ which is a little concave behind to the middle but on 

 the basal part decidedly convex and is covered on the entire posterior 

 side with soft dark hair ; outer forceps as usual in this group modified 

 into flat, shining plates, which at the tip are somewhat drawn out to 

 form a palpus-like organ. Legs black ; middle tibia with two bristles 

 on the outer front side; hind tibia with an uneven row on the outer 

 side. Wing sub-hyaline; bend of fourth vein rather far from the 

 margin and with a long distinct fold; the bend is rectangular and the 

 apical cell is narrowly open at some distance before the apex ; base of 

 third vein with about five bristles. 



Length 6 mm. 



One male; Dead Run, Fairfax County, Virginia, August 27, 1914 

 (R. C. Shannon). 



Type.— Male, Cat. No. 25713, U.S.N.M. 



PHOROCERA SULCATA, new species. 



Male. — Front 0.29 of the head width; the sides with yellowish 

 gray pollen, paler on the sides of the face; frontal bristles 8 or 9, 

 fully meeting the ascending large bristles of the facial ridges, one 

 or two small bristles outside of the frontal rows. Antennae long, 

 blackish, the third joint about four times the second, wide at the 

 tip; arista thickened on the basal third; parafacials considerably 

 narrower than the third antennal joint; bucca not over one-fifth 

 the eye height; palpi yellow on the apical third, becoming blackish 

 basall}^ ; proboscis small and short. Thorax gray, pollinose, slightly 

 3^ellowisli on the dorsum which has the usual dark stripes when 

 viewed from behind; dorsocentrals 4, sternopleurals 3, small fourtii 

 is present on one side and slightly indicated on the other; ptero- 

 pleural with one small bristle. Abdomen wholly black in ground 

 color with silvery pollen on the second and third segments except 

 their apices, which in some lights are subshining; the fourth seg- 

 ment is shining on at least the apical half; first segment with a 

 small pair of median marginals, second segment with a large pair; 

 third segment with a marginal row of about ten; fourth segment 

 with spiny erect hairs becoming bristly toward the apex. Genital 

 segments black, the united inner forceps forming a narrow slender 

 straight organ which does not taper much until at extreme tip 

 which is curved forward on the back; it is deeply grooved behind 

 on the apical half, the basal half being filled out and slightly 

 ridged on the median line ; the outer forceps form shining, reddish- 

 brown plates which' are blackened and bristly at the tip ; the penis 

 is larger than in related forms; fifth sternite shining, black, 



