1 68 TJ^Ai\'SFORMATIONS OF INSECTS. 



moreover, peculiar movements, and especially that of curling them- 

 selves up, and they do this for hours during the great heat of the 

 day ; if they are alarmed, they cock up the end of their bodies 

 in a threatening manner, and the attitude doubtless frightens some 

 of their disturbers. The larvae eat the leaves of most plants, and 

 they collect together in colonies, and often do a great deal of 

 mischief 



When they have attained their full size, the larvee form cocoons 

 with silk, and glue the threads together so as to make stout and 

 hard cases ; and some of them are to be seen stuck between the 



LARVA OF A SAW-FLY. 



twigs and leaves or upon the small branches, whilst others are 

 placed in the ground. These ground cocoons, however, contain 

 pieces of stone and dust. Every caterpillar, as soon as its cocoon 

 is made, begins to transform itself into a chrysalis ; but the saw- 

 fly larvae remain inert and huddled up for several months after 

 having made their snug and safe hiding-places. The metamor- 

 phosis does not take place at once, but occurs some time or 

 other during the winter or early spring ; and when it is com- 

 plete, the fly escapes, usually by cutting the end of the cocoon 

 with its jaws, and, should it be a female, it soon begins to use 

 the ovipositor. It flies to and fro, seeking a proper place to 

 deposit its eggs in, and takes a great deal of pains to select a spot 

 where the nourishment of the future larvae will be at hand ; and 

 it is not simply satisfied, like the butterfly, with laying its eggs 

 on or near the plant upon which the young are to feed. The 



