64 COQUILLETT [450] 



vittae, abdomen elongate oval, fifth ventral segment destitute of spines 

 and of long bristles ; middle femora each bearing one long bristle on 

 the basal fifth of the anterior-under side and with short ones on the 

 remainder, with three long ones on the basal half of the posterior- 

 under side and with short ones on the apical half ; hind tibiae desti- 

 tute of bristles on the posterior side ; wings grayish hyaline, yellow in 

 the costal cell, the veins largely yellow, otherwise as in the male. 

 Length, 6 to 8 mm. Two pairs, taken in coition, July 10. 



Habitat. — Popof Island, Alaska. 



Type, — Cat. no. 5248, U. S. National Museum. 



Hylemyia simpla sp. nov. 



Black, the halteres yellow, lower part of front yellowish brown ; 

 frontal orbits contiguous for a short distance, antennae nearly as long 

 as the face, the third joint only slightly longer than the second, longest 

 hairs of arista scarcely longer than greatest diameter of the arista ; 

 proboscis short and rather slender, labella large; mesonotum sub- 

 opaque, thinly dark grayish pruinose, the sides in front of wings light 

 gray pruinose, three pairs of postsutural dorsocentral bristles, sterno- 

 pleurals i + 2 ; abdomen depressed, nearly linear, dark gray pruinose, 

 the first segment and a median vitta, black, hairs of venter slightly in- 

 creasing in length toward its apex, hypopygium gray pruinose, destitute 

 of long bristles on its apical portion; front tibiae each bearing a bristle 

 near the middle of its inner-posterior side, the bristle at apex of inner 

 side sharp-pointed; middle femora on the anterior-under side and 

 apical half of the posterior-under side ciliate with rather short bristles, 

 on the basal half of the posterior-under side with very long ones ; 

 middle tibiae each bearing one bristle on the inner-anterior side, one 

 on the outer-anterior, one on the outer-posterior, and two on the inner- 

 posterior side, all near the middle of the tibia ; hind femora sparsely 

 ciliate on the anterior-under side with rather long bristles, the poste- 

 rior-under side with very short ones and near the apex with two or 

 three rather long ones ; hind tibiae each bearing about six rather short 

 bristles on the anterior-inner side, five on the anterior-outer side, three 

 long ones on the outer side, the Inner-posterior side ciliate with rather 

 short ones on the basal three- fourths ; wings hyaline, costal vein ciliate 

 with very short spines, costal spine much longer than the small cross- 

 vein, hind crossvein almost straight, calypteres yellowish ; length, 5 

 mm. A male specimen, collected June 16. 



Habitat. — Sitka, Alaska. 



Type. — Cat. no. 5249, U. S. National Museum. 



