July, 1908.] 



CATERPILLARS INJURING FOLIAGE. 



211 



already molted four or five times during growth, and the cast 

 skin is tucked away at one end of the cocoon. With this molt 

 the caterpillar has transformed to the pupa, similar to the 

 chrysalis of butterflies. In 1905 the caterpillars pupated about 

 September 7. In the pupa stage the insect remains dormant 

 throughout the winter, the moths emerging from the pupa? in 



Fig. 4. The Fall Webworm. Moth and cocoons, natural size. 



June, as already described, June 9 and 10 being the exact dates 

 at Durham in 1906. 



Further south there are two broods in a season, but in New 

 Hampshire but one seems to occur. 



REMEDIES. 



Spraying. — ^When the caterpillars are first noticed at work on 

 the tips of the twigs, if they seem to be abundant, it is best to 

 spray the tree with an arsenical. Arsenate of lead, five pounds 

 to the barrel of water, is best, though Paris green, at the rate of 



