170 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 90 



medial annuli black, these sometimes poorly defined and almost 

 wholly replaced by the lighter ground color. Antenna fuscous with 

 grayish or white annulations. Head light fawn, the scales tipped 

 with sordid white. Thorax light fuscous, the scales tipped with 

 gray or white; anteriorly the fuscous is more pronounced. Fore 

 wing with costal third fuscous mixed with gray, remainder light to 

 dark fawn irrorated with fuscous and gray; toward apex the colors 

 merge and are indistinguishable; at base, in anal angle, a small 

 blackish-fuscous patch; in cell a series of three blackish-fuscous 

 spots, sometimes confluent, forming a single longitudinal dash; cilia 

 grayish fuscous with a broad, dark, subbasal band. Legs creamy 

 white, strongly overlaid with fuscous except at joints. Abdomen 

 silvery grayish above; creamy white beneath suffused with fuscous 

 laterally. 



Male genitalia. — Harpe broad, with very few coarse hairs ; cucullus 

 rounded, densely clothed with coarse, stiff hairs; before cucullus, 

 from costa, a prominent dull-pointed projection; clasper minute; 

 emitting a few long hairs ; sacculus broadly folded and without basal 

 process. Anellus a moderately small sclerotized plate, constricted 

 at middle ; anterior and posterior edges strongly convex. Vinculum 

 broad, rounded. Aedeagus long, slightly curved, terminating in a 

 long, attenuated point ; vesica armed with a cluster of straight, strong 

 cornuti. Transtilla a very broad, sclerotized band with well-devel- 

 oped hairy lobes, the whole fused with the posterior portion of the 

 anellus. Socii small, narrow, hairy lobes. 



Female genitalia. — Genital plate moderately broad. Ostium large, 

 round, situated at the extreme anterior edge of the genital plate. A 

 narrow area of the ductus bursae, just posterior to the bursa copulatrix, 

 moderately sclerotized, unarmed; the remainder of the ductus mem- 

 branous; inception of the ductus seminalis about midway between 

 the sclerotized part of the ductus bursae and the ostium. Bursa copu- 

 latrix large with a very small signum in the anterior half. 



Alar expanse, 12.5-19 mm. 



Tyfe.—\n the United States National Museum. 



Type locality. — Snake River, Wliitman County, opposite Clarkston, 

 Wash. 



Food plant. — Artemisia dracunculoides Pursh. 



DistHl)Ution.—^OYi\mQsiQvr]. United States and southwestern 

 Canada. 



United States records 

 Washington: Almota, Whitman County, 12 $ $ , 12 9 ? (5-23-IV-34) ; Snake 

 River, Whitman County, opposite Clarkston, 5 $ $, 1 9 9 (February to 

 May dates, 1931-32 ; the February and March dates are for specimens reared 

 in a greenhouse) ; Truax, Whitman County, 7 5 5 , 10 9 9 (4-12-V-35) . (All 

 these specimens were reared from larvae collected by the writer.) 



