286 AMERICAN MICRO-LEPIDOPTERA. 



Hindwings, cilia and upper side of abdomen gray. Hind tibiae reddish gray, 

 their tarsi white, with broad black annexations. 



Female. The female shows the following differences: face and palpi white, 

 antennae white, grayish toward the apex. Tuft white, with a few brown scales. 

 Thorax and basal portion of the wings almost pure white. The apical portion of 

 the wings is also more suffused with white. Hindwings and cilia almost pure 

 white. Abdomen silvery gray. Legs white, tarsi with black annulatious. 



Type. No. 12002, U. S. Nat. Mus. 



San Mateo Co., California. Two specimens bred from Arbutus 

 menziesii in September, and bearing the record number 243. 



Lithocolletis obscuricostella Clemens. 



Plate XXI, Fig. 13. 

 Lithocolletis obscuricostella Clemens, Proc. Acad. Nat. Sci. Phil., 321, 1859. Tin. 



No. Am., 64, 71, 1872. Chambers, Can. Ent., iii, 85, 1871 ; xi, 92, 1879. 



Busck, Proc. Ent. Soc. Wash., v, 188, 1903. 

 Syn. virginiella Chambers, Can. Ent., iii, 84, 1871. Dyar, Bull. 52, U. S. Nat. 



Mus., 1902, No. 6280. 



"Head and frontal tuft silvery. Thorax very pale golden. Forewings pale 

 golden with a silvery median stripe from the base, black margined toward the 

 costa, extending to the middle of the wing ; with four silvery costal streaks, the 

 first very oblique and rather long, and all except the last black margined inter- 

 nally, the margin of the first being long and the continuation of a black streak 

 from the base along the extreme costa. Three silvery dorsal streaks, the first 

 quite long, obliquely curved and opposite the first costal streak, and the first two 

 black margined internally ; the second dorsal obliquely opposite the third costal 

 streak. Apical spot black; hinder marginal line black, cilia grayish. Hind 

 wings bluish gray, cilia the same. Abdomen black, tipped freely with yellow." 



The above is Clemens' description. 



The small tentiform mines of this species may be found on the 

 underside of the leaves of Ostrya Virginiana (Mill.) Willd. They 

 are usually between two veins and are less wrinkled than those of 

 the other species, mining the same leaves, viz. : L. ostrycefoliella. 

 The pupa is formed inside of a thin silken web which occupies an 

 entire half of the mine. Expanse of the imago 6-6.5 mm. 



I have some specimens in which the entire abdomen is pale grayish 

 yellow, but which otherwise agree with Clemens' description. 



Lithocolletis ostrysefoliella Clemens. 



Plate XXI, Fig. 14. 



Lithocolletis ostrysefoliella Clemens, Proc. Acad. Nat. Sci. Phil., 322, 1859. Tin. 

 No. Am., 64, 71, 1872. Chambers, Can. Ent., iii, 85, 1871. Cin. Quart. 

 Jn. Sci., i, 202, 1874. Can. Ent., xi, 91, 1879. Walsingham, Ins. Life, 

 ii, 53, 1889. Busck, Proc. Ent. Soc. Wash., v, 188, 1903. Dyar, Bull. 

 52, U. S. Nat. Mus., 1902, No. 6275. 



