134 



Forty-fifth Report on the State Museum. 



The Insect at Scottsville. 

 The attack was recognized as identical with one that had come under 

 my notice in the summer of 1886, through a letter and examples of the 

 eaten foliage of a yellow birch, JBetula lutea, and the infesting insect, 

 received from Mr, Shelby Reed, of Scottsville, Moni'oe county, N. Y., as 

 was briefly noticed in my " Third Report," as above cited, Mr. Reed, 

 writing September 14th, stated : " Trees infested with the insect have 

 a brown and scorched appearance, and light comes down through the 

 thickest of the foliage as through a softened skylight." 



The leaves sent for showing the injury to the foliage caused by the 

 insect, had very nearly all of the green parenchymal matter eaten away, 

 leaving only the transparent epidermis of one side as a thin transparent 



film. In a few instances only, 

 had this film been broken or 

 pierced into holes of micro- 

 scopic size. It was interesting 

 to see how thorough had been 

 the work of dissecting out the 

 parenchyma from between the 

 epidermal reticulations. Only 

 here and there had a cell 

 escaped — all of them united, 

 over the entire surface of some 

 of the leaves, not exceeding a 

 square quarter-inch. It was 

 the most remarkable and 

 beautiful leaf dissection that 

 had ever come under my ob- 

 servation, far exceeding in 

 delicacy any of the " skeleton- 

 . J izing " which we are often 



Fig. 2.— BucculatrixCanadhnsisella: «, skeletonized ° 



leaf; h, molting cocoon; c. larva; d, head of larva; called upon tO admire. That it 

 e, anal segments of larva; /, same of pupa; <;, cocoon ^^^^^^ ^^^^ ^^^^ executed by 

 with extruded pupa skin; ?i, moth — all enlarged. •' 



(From Insect Life.) SO Small a larva, seemed sur- 



prising, until it was learned from Mr. Reed that it was the concerted 

 work of large numbers — forty-eight of the little caterpillars having 

 been counted by him on a single leaf. 



The leaves of the cut leaf birch received from Ausable Forks, were 

 less eaten than the above — only about one-half, on an average, of the 

 parenchymal matter having been removed. It is probable that the 

 native birches, in their ''burned looking" foliage, had been more 

 seriously affected. At a, in Figure 2, a partly skeletonized leaf is shown. 



