D PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 64. 



trochanters light gray pruinose; remainder of the legs black. Wings 

 long and narrow, slightly less so than in E. angustipennis Alexander 

 (Canadian North-west Territories), faintly tinged with brown; 

 cells C and Sc a little more yellowish; stigma lacking; veins dark 

 brown, Sc more yellowish. Venation: Scj^ ending just before r 

 which is very faint; i?2+3 from two to four times the deflection of 

 .B4+5 and one-half longer than the first section of R2; basal deflection 

 of Cui at or just before the fork of M; fusion of J/3 and Cui variable, 

 from one to nearly two times the basal deflection of Cu^; vein 2d A 

 short and straight ending just beyond the origin of Rs. 



Abdomen dark, conspicuously dull gray pruinose; hypopygium 

 conspicuously reddish brown. Male hypopygium with the ninth 

 tergite relatively small with a deep U-shaped median notch, the lobes 

 with conspicuous setae. Pleurites slender, the ventral angle not so 

 conspicuously produced as in related species; outer pleural appendage 

 a powerful arm that rapidly narrows to the subacute black apex, the 

 outer face microscopically squamulose, the mesal or inner face near 

 midlength dilated into a conspicuous, elongate-triangular blade that 

 is about as long as the apex itself; viewed laterally the entire distal 

 end of the appendage appears triangularly dilated; iimer pleural ap- 

 pendage a straight rod, the apex subtruncate and narrowly black- 

 ened, bearing a single seta. Penis-guard and gonapophyses slender, 

 straight, subequal in length, the apophyses pale with the heads 

 slightly enlarged, bearing on the mesal apical angle and along the 

 mesal margin abundant short setae. 



Described from two males collected by J. M. Aldrich in Alaska: 

 one at Valdez, June 8, 1921, the other at Camp 327, Alaska Engineer 

 Commission, (since named Windy, a siding on the Alaska Rail- 

 road), July 12, 1921. 



Type.—Usile, Cat. No. 26083, U.S.N.M. 



ERIOPTERA (ERIOPTERA) DYARI, new species. 



Allied to E. villosa Osten Sacken; eyes of male widely separated 

 by the vertex; vertex yellow with a brown spot; general coloration 

 pale brown, variegated with sulphur-yellow; male hypopygium 

 with the inner pleural appendage curved before the tip, the apex 

 suddenly narrowed into a powerful spine; outer gonapophyses 

 cultriform. 



Male. — Length about 5.2 mm.; wing 6.5 mm. 



Rostrum and palpi dark brown. Antennae light brown; eyes of 

 the male not conspicuously enlarged, widely separated by the vertex. 

 Head yellow, the center of the vertex with a conspicuous brown 

 spot. 



Pronotum yellow, infuscated medially. Mesonotal praescutum 

 very pale brownish, sparsely pollinose, the lateral margins and 



