244 



THE LIFE OF AN INSECT. 



accomplish it, the change taking place under 

 water. They attach themselves to the leaves of 

 some of the younger aquatic plants, which are at 

 a suitable depth from the surface of the water. 

 By means of several silken cords the insect fastens 

 together two, and sometimes even three leaves, 

 between which it spins an oval cocoon, composed 

 of very white silk. This cocoon is of a double 

 structure ; the true inner cocoon, which is very 

 white, is placed within an outer envelope of silk, 

 of a greyish or brownish colour. The envelope 

 extends considerably beyond the sides of the true 



The Cut represents two leaves, between which the Worm lies, the Cocoon itself, and the Larva. 



cocoon (which lies loosely in it) ; and towards one 

 end there is a wide opening in it, the inner cocoon 

 being perfectly closed in on every side." The cut 

 on the next page represents the perfect insect and 

 the pupa thus carefully provided for. 



