INSECTS INJURIOUS TO ORCHARD FRUITS 



491 



" 



pillars hatching from an egg mass feed together on adjoining 



leaves, which they soon commence to draw together with silken 



threads, and by the 



first frosts they have 



spun them into a 



tough web. This is 



attached to the twig 



by the old leaf stems, 



which are bound to 



it by silk. The web 



looks like a couple of 



dead leaves from a 



distance, but the 



leaves are merely the 



FIG. 415. Full-grown larvae of the brown-tail 

 moth natural size. 



outer covering, and if 

 the silk web be torn 

 open, there will be found numerous small pellets of silk each enclos- 

 ing from three to twelve of the little partly grown caterpillars. The 



caterpillars emerge just as 

 the buds burst in the spring 

 and feed on the expanding 

 foliage. Where abundant 

 they soon strip a tree, for 

 each of the nests harbors 

 400 or 500 little caterpil- 

 lars. In five or six weeks 

 they have become full 

 grown and spin thin 

 cocoons of white silk among 

 the leaves, in which they 

 transform to dark-brown 

 pupae. About three weeks 

 later the moths emerge. 



Several native parasites 

 and predaceous bugs prey 



..,- r , , M ,1 /E , upon the caterpillars, but 



FIG. 416. The brown-tail moth (Euproctis * . ' 



chrysorrhcea Linn.): male above, female do not seem materially to 



below natural size. reduce their numbers. 



In Europe there are several parasites which prey on all stages 



of the insect and which the State of Massachusetts with the 



