ANNETTE F. BRAUN. 317 



ous in the summer form. Abdomen gray, with ocherous apex. 

 Legs varying from pale whitish ocherous to gray, their tarsi whitish 

 at the bases, grayish brown toward the apices. 



This species is probably found over the whole of the United 

 States. In the U. S. Nat. Mus. is a series bred by Dr. Dyar at 

 Denver, Colorado, on cotton wood in July, 1901, and a specimen 

 from California on Salix (collection C. V. Kiley). 



The food plants are various species of Salix and Populus, the 

 mine being placed on the lower side of the leaf. The imagoes of 

 the fall brood, which appear in October, hibernate. 



This is an exceedingly variable species, so variable in fact, that 

 specimens of the different broods may easily be mistaken for distinct 

 species. The differences are due to a variation in the extent of the 

 white markings, and in the black dusting, some specimens lacking 

 entirely the black dusting typical of the species. 



I have bred series of this species in successive broods from tenti- 

 form mines on the underside of leaves of Populus balsamifera L. 

 In the imagoes which appear in August, the black dusting is almost 

 or entirely lacking. One of these is represented on Plate XXIII, 

 Fig. 3. Such specimens are identical with those bred by Dr. Dyar 

 in Colorado. In this form the tuft and thorax are often pure white, 

 and very often the first dorsal streak is widely separated from the 

 first costal streak, with which it is usually confluent in the dusted 

 specimens. 



Zeller, in his description of atomariella, and Chambers, in his 

 earlier description (Can. Ent., iii, 163, 1871), regarded white as the 

 ground color of the wings. Zeller's two types at Cambridge are 

 identical with Chambers' specimens, which represent the dusted 

 form of the species (Plate XXIII, Fig. 2). The Zeller type at the 

 U. S. Nat. Mus. (Plate XXIV, Fig. 24) has a greater extent of 

 the wing occupied by the white markings. 



Lithocolletis tremuloidiella Bratm. 



Plate XXIII, Fig. 4. 

 Lithocolletis tremuloidiella Braun, Ent. News, xix, 102, 1908. 



Antennae dark gray, the joints becoming lighter toward their bases. Palpi 

 grayish white. Face grayish white. Tuft gray, mixed with white. 



Forewings pale reddish brown near the base, becoming more ocherous beyond 

 the middle. There is a short median basal white streak, and a dorso-basal white 

 streak, both thickly dusted with blackish scales, and uniting with the first dor- 



TRANS. AM. KNT. SOC., XXXIV. OCTOBER, 1908. 



