IO4 THE INSECT WORLD. 



by the liquids which are contained in the insect which has just 

 emerged, and whose wings are no longer confined in their cases. At 

 the time of its birth the wings are flat and thick ; as they grow, little 

 by little they spread themselves out and become curled up. When 

 they are completely developed and flattened the wings become firm 

 and hard imperceptibly, and this firmness extends at the same time 

 to the whole of the body. 



Figs. 131 and 132, borrowed, like the preceding, from the i4th 



Fig. 131. Moth whose wings are developing. Fig. 132. Moth whose wings are developed. 



Memoir of Reaumur (sur la transformation des chrysalides en papillons), 

 show the states through which the wings of the same moth pass, 

 before they are thoroughly developed. 



Those pupae enclosed in cocoons free themselves entirely or in 

 part from their old skin, in the shell itself; but the imago is still a 

 prisoner. It has broken through a first enclosure ; it must open 

 itself a way through the second. How does it manage to bore 

 through the often very solid walls of this second prison, so as to 

 regain its liberty ? Reaumur states that in the Lackey Moth {Bombyx 

 neustria) the head is the only instrument of which the insect makes 

 use in opening a passage, the compound eyes then acting like files. 

 These files cut the very fine threads of which the cocoon is composed, 

 and as soon as the end of the cocoon is pierced through, the insect 

 uses its thorax like a wedge, to enlarge the hole. It very soon 

 manages to get its two front legs out, fixes itself by them on to the 

 outside, and little by little emerges from its prison. 



