206 



INSECT LIFE. 



of the young student represent two groups — the leaf- 

 rollers and the leaf-miners. 



THE LEAF-ROLLERS. 



If the pupil will examine the leaves of almost any 

 forest tree during the summer or autumn 

 he will find that some of them are rolled 

 in such a way as to form a nest, within 

 which one or more larvae live or have 

 lived. These nests vary greatly in form ; 

 sometimes a single leaf, or even only a 

 part of a leaf, is rolled ; in other cases 

 the nest is formed by fastening together 

 several leaves. In most cases the build- 

 ing of the nest is the work of a single 

 larva, but in very many instances several 

 larvae work together to build a common 

 nest. It should be said, however, that 

 each of the leaf-rolling species builds a 

 nest of a particular form, and each of 

 these species infests a certain kind or 

 kinds of trees. Hence, when a student 

 has carefully studied the life history of a 

 leaf-roller, he will be able, as a rule, to 

 recognize the work of this species by a 

 study of the nest alone. 



In making its nest the leaf-roller fast- 

 ens the folds of its nest in the desired 

 position by means of little bands of silk. 

 Several of these bands are shown in Fig. 

 175, and in Fig. 176 are represented sev- 

 eral types of nests made of rolled leaves. 



The breeding of leaf-rollers is somewhat more 



Fig. 175. 



