88 Annals Entomological Society of America [Vol. XI, 



riorly; posterior cross vein a little before the middle of the discal cell; 

 fifth vein incurved at the tip. Length, male 9 mm. ; wing 9 mm." 



"Habitat: Unalaska, three males. (Kincaid) Type No. 145. Wash. 

 Agric. Coll. and S. of S." 



Hypopygium (Figs. 15-17). — Mr. Alexander has very 

 kindly aided in interpreting the relationships and disposition 

 of the various sclerites which compose the hypopygium. In a 

 letter under date of Sept. 26, 1917, he gives a lucid explanation 

 of the whole structure. 



Fig. 18. Adult female. X 6.5. 



"The ninth tergite (Fig. 17) large, prominent, the caudal margin 

 with a deep, broad notch, the adjacent lobes rounded at their apices. 

 Ninth pleurite (9 pi) (Figs. 15 and 16, pi.) prominent, the inner margin at 

 the tip produced caudad into a small flattened blade {bl.), a projection 

 of the pleurite; pleural appendage {pi. app.) large; fleshy lobe (/.), on 

 dorsal face of pleurite densely beset with fine hairs. Ninth stemite 

 (9 St.) small, deeply split on the mid-ventral line by a very acute angle. 

 Penis guard {p. g.) trifid with numerous appressed teeth on the inner 

 edge of the lateral arms." 



