ATTACKING THE LEAVES. 



265 



Fig. 275. 



those of the female thread-like. Fig. 274 represents the male. 



Should this insect ever prove destructive, it may be subdued 



by the treatment recommended for No. 140, the species last 



described. 



No. 142. — The American Procris. 



Pi^ocris Americana Harris. 



The larvae of this destructive insect feed in flocks, arranged 

 in a single row on the under side of the vine leaves, as shown 

 in Fig. 275. The egg-clusters from which these larvae pro- 

 ceed, consisting of 

 twenty eggs or more, 

 are fastened by the 

 moth to the under 

 side of the leaves. 

 While young, the 

 little caterpillars eat 

 only the soft tissues 

 of the leaves, leavi ng 

 the fine net- work of 

 veins untouched, as 

 shown on the right 

 of the figure, but 

 as they grow older 

 they devour all but 

 the larger veins, as 

 shown on the oppo- 

 site side. They acquire full growth in August, when they 

 measure about six-tenths of an inch in length, are of a yellow 

 color, slightly hairy (see Fig. 276, a), with a transverse row 

 of black spots on each segment ; they feed with their heads 

 towards the margin, and gradually retreat as the leaf is de- 

 voured. When full grown, they disperse, and, retiring to 

 some sheltered spot or crevice, construct their tough, oblong- 

 oval cocoons, one of which is shown at c in the figure, within 

 which in about three days they change to shining brown chrys- 

 alids (6) about three-tenths of an inch long, from which the 



