318 AMERICAN MICROLEPIDOPTERA. 



sal streak. There are five costal and five dorsal white streaks, all dark margined 

 internally and more or less dusted with blackish scales, the last two pair, how- 

 ever, not dusted. These streaks are situated as follows: a large oblique white 

 costal streak at the basal fifth, attaining the middle of the wing and prolonged 

 backward ; nearer the base an oblique dorsal streak, almost meeting the first 

 costal before the middle; the second costal streak also oblique; the second dorsal 

 streak nearer the base than the second costal, large, oblique, strongly constricted 

 just below the fold, and uniting with the apices of the first and second costal 

 streaks; third costal and dorsal streaks nearly opposite, less oblique, their apices 

 separated by a narrow prolongation of the blackish internal margins. The 

 fourth costal and dorsal streaks, of which the costal is at the apical fourth, the 

 dorsal at the tornus, form an inwardly convex white fascia. Fifth costal and 

 dorsal streaks also form a curved white fascia. An irregular blackish apical 

 spot. Marginal line in the cilia blackish, with a bluish lustre. Cilia gray. Alar 

 expanse 9-10.5 mm. 



Hindwings gray. Cilia gray, with a reddish tinge. Abdomen dark gray 

 above, grayish white beneath. Anal tuft grayish ocherous. Legs dark gray, 

 tips of the tarsi lighter. 



Described from specimens bred by Mr. W. D. Kearfott from 

 tentiform mines on the underside of leaves of Populus tremuloides 

 Michx., received from Mr. J. W. Cockle, Kaslo, B. C., August 26, 

 1907. The imagoes appeared during the same month. The mine 

 is large (for an underside Lithocolletis mine), oval, and with a fine 

 fold through its long axis. It closely resembles the mine of L. 

 salieifoliella on poplar, but is very much larger. 



There is considerable variation in the extent of the white mark- 

 ings ; sometimes the fascia formed by the fourth pair of streaks is 

 interrupted, and the fascia just before the apex does not reach the 

 inner margin. 



This species is very close to L. salieifoliella in the character and 

 arrangement of markings ; but may be distinguished from it by the 

 much greater expanse, the slightly shining and more reddish ground 

 color of the forewings, the slightly less oblique position of the white 

 streaks, and by the noticeable bluish lustre of the marginal line in 

 the cilia. The specimens which appear in August are densely 

 dusted, in this respect differing from the corresponding brood of L. 

 salieifoliella. 



By some mistake, this species has been referred to as Lithocolletis 

 populiella Chambers by Mr. Busck in his paper, " Tineid Moths 

 from British Columbia" (Proc. U. S. Nat. Mus., xxvii, 770, 1904), 

 and by Dr. Harrison G. Dyar in " Lepidoptera of the Kootenai 

 District" (Proc. U. S. Nat. Mus., xxvii, 937, 1904). 



