CH. XV.] THE CATERPILLAR. 257 



inside of the case with its hind-legs, detaches it in- 

 stantly from its original place, and drags it forward : 

 it advances thus gradually, and at length fixes the 

 case with silken cords, either to another leaf or an- 

 other part of the same leaf, containing a fresh sup- 

 ply of provisions. The annexed figure gives a re- 

 presentation of the different operations which have 

 been just described. In the first (fig. 1) the worm 

 is seen between the thin membranes of the leaf and 

 destitute of its coat ; the second (2) shows the com- 

 mencement of the cutting process ; the third (3) re- 

 presents the work in a state considerably advanced ; 

 the insect being engaged in converting it from a 

 plane into a cylinder ; in the fourth (4) it is seen en- 

 deavouring to detach its finished mantle from the 

 leaf; the last is a distinct representation of the little 

 animal enveloped in its new coat. 



j> 



As soon as the insect has fastened its mantle, or, 

 as it may be properly called, its tent, to a fresh por- 

 tion of a leaf on which it intends to feed, it pierces 

 the outer skin or epidermis, eats only the juicy sub- 

 stance contained between the two membranes of the 

 leaf, and sedulously avoids doing the slightest injury 

 to the upper membrane ; it gradually extends its ex- 

 cursions in search of food, considerably beyond the 

 Y2 



