LEPIDOPTERA OF NEW YORK AND NEIGHBORING STATES 93 



There is considerable variation in the size of the white spots ana it is but rarely 

 that they form a fascia. Females may be distinguished from specimens of N. clem- 

 ensella by their larger size, and the males from that species and all others except 

 A 7 , similella, by the peculiar chitinous plate along the costa of the hind wing. 



33. Nepticula clemensella Chambers. Tuft ochraceous; eye-caps silvery white. 

 Fore wings bluish black. A narrow, oblique, silvery streak on the middle of the 

 costa (rarely inconspicuous) and an opposite dorsal streak, usually meeting in 

 the male to form a narrow, oblique fascia. Cilia silvery with a brown line formed 

 by the dark tips of the terminal row of scales around the apex. Hind wings 

 yellowish fuscous, similar in both sexes. 4.5 to 5.2 mm. 



The larva mines in the leaves of sycamore (Platanus occidentalis) , forming a 

 linear mine which gradually increases in breadth. Its terminal portion expands 

 into a small blotch, three or four times the diameter of the end of the linear mine. 

 There are three generations a year. 



This species is much less common than N. platanella and uniformly smaller, the 

 largest specimens scarcely attaining the expanse of the smallest N. platanetla. 



34. Nepticula similella Braun. Tuft ocherous to ochraceous; eye-caps silvery 

 white, occasionally tinged with ocher. Thorax and fore wings deep bluish black, 

 the extreme bases of the scales more or less iridescent blue, especially in the 

 apical half of the wing. At the middle of the wing an oblique narrow, costal 

 streak, shining white but not silvery, usually meets the apex of a shorter, broader, 

 dorsal streak. Tips only of the last row of scales around apex dark, thus forming 

 a dark line in the white cilia. Hind wings gray; in the male with a narrow, 

 chitinous . plate from base to one -third of costa, with a long, yellowish, costal 

 hair-pencil lying along it. 5 to 6 mm. 



Ohio; Kentucky. 



The larva makes a characteristic mine in the leaves of pin oak (Quercus palus- 

 tris) and occasionally of chestnut. The early part of the mine is very narrow, 

 completely filled with frass, and bent several times in close, S-shaped curves. The 

 larva next mines just above the lower epidermis, forming a blotch scarcely visible 

 above except for occasional spots here and there toward the edges of the blotch, 

 where the leaf substance is more fully consumed. During the last stage, a con- 

 spicuous large blotch is formed, where the mine is transparent and whitish, with 

 the frass accumulated toward the beginning of the blotch. 



Females of this species can only be distinguished from those of N. platanella 

 by their less shining costal and dorsal spots; the males differ in the yellowish 

 costal hair-pencil of their hind wings. 



35. Nepticula thoracealbella Chambers. Tuft ochraceous on the face, becoming 

 reddish brown on the vertex; eye-caps white. Thorax white, with a few, scattered, 

 dark brown scales in occasional specimens. Fore wings dark brown, slightly irro- 

 rated; a creamy white, irregular fascia just before the middle, concave toward 

 the base and usually wider on the dorsal margin; at the apical fourth a distinct, 

 creamy-white, costal spot, and an opposite dorsal spot, whose apices occasionally 

 touch; cilia creamy white, sometimes grayish on the dorsum. 4 to 5 mm. 



Kentucky ; Ohio ; Pennsylvania. 



36. Nepticula pomivorella Packard. Tuft orange -ochraceous; eye-caps and collar 

 shining pale buff. Thorax and fore wings shining bronzy, with strong purple and 

 blue reflections increasing toward the apex. 5 mm. 



The larvae make long, narrow, serpentine tracks (fig. 61) in the leaves of apple, 

 gradually widening the mine to 2 or 2.5 mm. at the end. 



37. Nepticula chalybeia Braun. Tuft ocherous, sometimes shading to reddish 

 brown above; collar yellowish white; antennae fuscous; eye-caps yellowish white. 

 Thorax steel-gray. Fore wings very narrow, steel-gray with faint, greenish golden 

 reflections. 3.5 to 4 mm. 



Ohio. 



