2 ' BULLETIN 435, U. S. DEPARTMENT OF AGKICULTTJRE. 



HISTORY. 



This species was first described by Clemens, in 1860, under the 

 name of Anchylopera nubeculana Clem. In 1875 Zeller described the 

 adult, pupa, and larva under the name of Phoxopteris nubeculana. 

 The first record of injury caused by this species is given by Riley, 

 who called it by the common name of ''apple leaf-sewer," in his 

 annual report of 1878, the injury occurring in Ontario County, N. Y., 

 where certain orchards were seriously affected, one-fourth of the 

 leaves being infested. In 1878 P. II. Hoy reported it a serious orchard 

 pest in Wisconsin, while Lugger, in 1899, reported injury by this 

 insect in Minnesota. The moth has also been recorded as abundant 

 in Ontario (Canada) orchards in 1895 and 1903. Felt in 1907 re- 

 corded the ravages of the insect in New York State and gave meas- 

 ures for its control. SUngerland and Crosby have given a short ac- 

 count of the apple leaf sewer In their recent "Manual of Fruit In- 



DISTRIBUTION. 



Dyar gives the distribution of this species as ''North Atlantic 

 States." Fernald received it from Nova Scotia (Canada), while 

 Rounthwaite collected it in Manitoba and Fletcher recorded it from 

 Ontario. In the United States, specimens in the United States Na- 

 tional Museum, the correspondence, notes, and collection of the Bu- 

 reau of Entomology, and the available literature, all indicate that 

 this species occurs in the following States: Connecticut, Illinois, 

 Maine, Massachusetts, Michigan, Minnesota, Missouri, New Hamp- 

 shire, New Jersey, New York, Pennsylvania, Rhode Island, Virginia, 

 and Wisconsin. 



FEEDING HABITS AND CHARACTER OF INJURY. 



This insect appears to confine its attack to the apple. 



Immediately on leaving the egg the larva migrates to the vicinity 

 of one of the prominent main ribs on the underside of the leaf and 

 spins a sheltering web of silk, under which it begins to feed (fig. 1,5). 

 The larva never feeds before completing its shelter of silk, and during 

 the first 3 or 4 weeks of its life does not leave this silken covering, 

 but extends it from time to time over the tender parenchymatous 

 tissue on the underside of the leaf, gradually drawing the lower 

 sides of the leaf together (fig. 2). At the end of this period, the 

 young larva, having increased very materially in size, gnaws 

 through the upper tissues of the leaf and makes its way to a, 

 fresh leaf, usually the one directly above. Here it stations itself 

 on the upper side of the leaf at the juncture of the midrib and 

 stem and spins another web of silk. Each strand crosses the 

 midril) at right angles, and both ends of each strand are fastened 



