APPLE INSECTS — BUDS AND FOLIAGE 57 



nearly f of an inch in length. It then comes out of this mine 

 and makes a thin, white, silken molting cocoon (Fig. 62), 

 within which its skin is shed in a few days, and the greenish- 

 brown caterpillar feeds openly on the surface of the leaves 

 near the edges. A second larger molting cocoon is made in 

 about 4 days. Two days later the caterpillars appear in their 

 last stage niid proceed to skeletonize the foliage for about a 



lMi||# 



Fig. 62. — Apple leaf showing mines and "molting cocoons" of the caterpillars, 



enlarged. 



week, finally wandering about to find a suitable place to spin 

 their true ribbed cocoons early in July on the leaves, young fruits 

 or twigs and larger limbs. It requires 3 or 4 hours to build one 

 of these ribbed cocoons (Fig. 63). The pupal stage lasts from 

 1 to 2 weeks in these summer cocoons, most of the moths emerg- 

 ing by August 1 in New York. The mines of the young cater- 

 pillars are usually near the centers of the leaves, while most of 

 the skeletonizing is done near the edges and always on the upper 

 surface. When badly eaten, the leaves turn brown and curl. 

 The caterpillars often hang suspended from the leaves by silken 



