58 FRIT IT INSECTS 



threads, and may be blown on to otluT food-plants near by, 

 where their cocoons are sometimes found. 



In Maine there is apparently but one^ brood of this insect 

 annually, as the moths did not appear until spring from pupse 

 formed August 1. In southern New York, however, there are 

 two distinct broods, the moths emerging in July lay eggs early 

 in August and the second brood of caterpillars work on the leaves 

 during August and September in the same manner as the first 

 brood. Being more numerous, the work of the second brood is 



Fk;. 6."->. — Tho ribbed cocoou-niakcr biiildiufi; its roeoon. Enlarged. 



usually more conspicuous and extensive than that of the spring 

 brood. Eighty per cent of the cocoons made in autumn ar(^ 

 within two feet of the ends of the branches on the lower third 

 of the trees. 



The summer brood is far less liable to be attacked by parasites 

 and diseases, moths emerging from 80 to 90 per cent of the cocoons 

 in July, whereas it is unusual for moths to emerge from more 

 than 50 per cent of the winter cocoons. Five tiny hymenopter- 

 ous parasites, Cirrospilus flavicindus, Encyrtus bucculatricis, 

 Mesochorus politus, Apanteles caccecice and Zaporus sp., play 

 an important part in checking this pest. Many of the cocoons 

 are often stripped from the twigs by birds in winter, and in 



