66 



INSECT RECORD FOR 1899 



Kather early in spring, soon after the leaf-growth is well 

 started, the colonies of tiny caterpillars hatch from eggs — laid 

 apparently the season before — and congregate upon one or 

 two leaves. They roll these np by means of silken threads and 

 cat the green surface on the inside of the roll. As they grow 

 they draw together neighboring leaves, feeding on their sub- 

 stance, and continually spinning the silken threads that form 

 the tent. The condition of the tent when the caterpillars are 



about half 

 grown is illus- 

 trated in Fig. 

 17. Late^ 



m ore leaves 

 and branches 

 are drawn to- 

 gether until 

 the tent form 

 is reached. 



By this time 

 the caterpil- 

 lars are gener- 

 ally full-grown 

 so far as this 

 larval state 

 is concerned. 

 They now re- 

 tire to the 

 middle of the 

 tent, where 

 about hall-grown. they unite to 



form a colony of cocoons side by side, more or less intermingled 

 with the dried particles of excrement. Within these cocoons 

 ihe larva? change to pupa?, the quiet stage in which they rest 

 and take no food. In about two weeks the pupa^ wriggle out 

 from the cocoons and reach the outer surface of the tent. 

 Then they split apart and the small orange-brown moths come 

 out. The empty pupa skins as they hang on the deserted 

 tents are shown in Fig. 18. 



Fig. 17. Chen y Tent in i)ioeess of lorniation : caterpillars 



