53 



shrubs, as well as those of the elm. After feeding for some weeks, 

 the larva? descend to the ground, in which it changes to a pupa, 

 coming out as a moth the following spring. The moth is about 

 two inches across the spread wings. Figure 40 shows the larva 

 feeding, copied from Dr. Lintner. 



CANKER WORMS. 



These familiar, and often most troublesome pests, often commit 

 great ravages upon the foliage of the elm. We have two cjuite 

 similar species of canker worms, which may be designated as 

 the spring canker worm, and the fall canker worm. Both are 

 very mischievous insects, but the spring species has been most so, 

 and in the many places no enemy of the elm has committed greater 

 apparent ravages, although these are of such a nature that if they 

 are not too long continued, the trees usually recover much ot their 

 original vigor in a few seasons. 



THE SPRING CANKER WOR^[. 



Aristopteryx vernata, Peck^ sometimes occurs in such mim- 

 bers that the trees are entirely stripped of their leaves. 1 have 

 seen rows of great elms as bare in June as they ordinarily are in 

 December. Fruit growers, also, are usually made aware of the 

 presence of this pest before they have had many years of experi- 

 ence. 



^W '^-/^'^S 



Figure 41. 



Anisopteryx veniata. 

 a. Male. b. Female. 



The only really redeeming quality which the canker worm pos- 

 sesses is the clumsy, wingless, and therefore immobile character of 

 the female. A few species of moths are found in which, although 

 the males have fully developed wings, and are very active, the fe- 

 males are destitute of wi;igs and can only creep slowlv from place 



