NOVEMBER, 1861. 171 



1. A. ostrycefoliella. The larvas may be found on the 

 leaves of iron-wood during the latter part of September and 

 early in October. 



About the 10th of October all the mines are untenanted. 

 There may be a spring brood in the leaves of the Ostrya, but 

 I have not observed them. 



The mine is large when compared to those found in the 

 leaves of other plants, and the hole left by cutting out the disk 

 is out of proportion to the size of the mined portion. 



2. A. saliciella. From the beginning to the middle of 

 July the larva may be taken on the leaves of yellow willow. 

 The mine is very small, the excised portion, with which the 

 disk is formed, taking up the greater portion of it. I noticed 

 in this larva a habit, which may be generic, but if so it has 

 escaped my observation : the larva, after cutting out its disk, 

 lets itself down by a thread, and in the middle of July the 

 disks may be found suspended under willows as the larva lets 

 itself down to the surface of the ground. My specimens 

 were taken on July 23rd, when the mines were generally 

 deserted. 



A larva of this genus mines the leaves of wild cherry in 

 July. The mines are usually near the base of the leaf, and 

 are more elongated than any others I have found. The mine 

 is a short tract, not broader than the short diameter of the 

 disk, which is cut out from the end of the mine, the hole 

 occupying its entire breadth. If the species is distinct, and 

 this I am disposed to doubt, it may be called A. pruniella. 



jNepticula. 



Habits of the Larva. 

 These larvas mine very narrow serpentine paths in the 

 interior of leaves, the mine being always on the upper sur- 

 face.* The mines vary much in form, being sometimes a 



* The larva of the European N. trimaculella mines indifferently both sur- 

 faces of the leaves of Populus nigra. H. T. S. 



