ORDER IV. MOTHS AND BUTTERFLIES. 



157 



wide, which is fastened securely to the twigs, and which is 



so strong that its outer Figure C3 



coat can not be torn 



with the fingers. The 



inside of this outer 



skin or covering is 



thickly lined with soft 



but strong brown silk, 



which may be woven 



and unwound like that 



of any Silk-worm, and 



surrounds a black, 



shining chrysalis, from 



which in due timo the 



Moth issues. 



Fig. 33 represents 

 the cocoon, and Fig. 

 34 its silk. 



These cocoons re- 

 main motionless on the 

 bushes until May or 

 June, and though oft- 

 en exposed in the open 

 air to a temperature as 

 low as 10 Fahr. they 

 are perfectly protect- 

 ed* Those which we 

 have raised in the house come out as early as April, be- 

 cause the warmth of the room develops them sooner. When 

 ready to emerge from its shell, the Moth throws out a caus- 

 tic liquid from its mouth, which destroys the fibres of silk 

 and enables it easily to pierce the upper end of its parch- 

 ment-like prison, from which it then creeps out with short, 

 damp antenna? and wings, which by continual moving be- 

 come dry and enlarged to their natural size. 



Cocoon of the Cecropis 



