286 THE LIFE OF AN INSECT. 



necessary to enable her to force her way through 

 this, to her, solid and resisting mass. Though 

 much attention has been paid to the transforma- 

 tions of this particular insect, it is somewhat 

 curious that it is still a matter on which opinions 

 are divided, as to how the insect succeeds in 

 making its egress. Some suppose that the eyes, 

 which are the only hard organs of the head, are 

 the instruments by which the threads are divided, 

 their numerous minute facets serving the purpose 

 of a file. Others hold the belief that the insect 

 pours out a fluid which acts upon the gum and 

 silken fibres of one end of the cocoon, and so 

 softens them that they easily give way to the 

 slightest pressure from within. " Perhaps the two 

 opinions," observe Messrs. Kirby and Spence, "may 

 be reconciled by supposing the silk-worm first 

 to moisten, and then to break, the threads of the 

 cocoon. In those that are of a slighter texture, 

 a mere push against the moistened end is probably 

 sufficient ; and hence we find in so many newly- 

 disclosed moths the hair in that part wet and 

 closely pressed down." 



It has been supposed, in cases where the 

 cocoon is a hard, almost wooden cell, that the 



