50 



INSECTS AFFECTING THE APPLE. 



and expanding scarcely half an inch, lay their eggs, 



probably, on the leaves 

 or tender twigs of the 

 apple, late in spring, or 

 early in summer. The 

 larva 1 soon hatch and 

 begin to eat the paren- 

 chyma of the leaves, 

 and as they grow older 

 they spin a slight pro- 

 tective silken web on 

 :■_. the upper surface of 

 the leaf, beneath which 



Fig. 19. Leaf-skeletonizer : a, larva; b. ... 



part of back, magnified to show thev continue their de- 



markings; c, head and front part 



of larva, magnified; d, moth, mag- striictive Work. AVlieil 



nifled. 



full grown (a) they vary 

 from an olive, or pale green color to brown, are 

 about half an inch long, and have four black shin- 

 ing tubercles on the back, just behind the head. 

 About midsummer these larva' pupate in slight 

 cocoons, formed usually on the leaf, and two weeks 

 later the moths emerge. Eggs are laid by these for 

 the second brood of larvae, which form cocoons be- 

 fore winter sets in, and hibernate as pupa', the moths 

 from them emerging the following spring. 



This species is very irregular in its development, 

 it being easy to find larva' of nearly all ages almost 

 any time during the season. The second brood is 

 usually much more numerous than the first, and 

 consequently the injury is most noticeable in Sep- 

 tember and ( )ctober. 



