VAPORER MOTH EGGS HOW DEPOSITED. 215 



adhere securely to the cocoon and to each other. They are ex- 

 truded in a continuous string, which is folded and matted 

 together so as to form an irregular mass. I once pierced one of 

 these females with a pin while she was in the act of depositing 

 her eggs; and so tenaciously did she adhere to them that for a 

 time it was uncertain whether the body would not tear asunder 

 before it would separate from the string. Within a day or two 

 after she comes out of the cocoon the female has completed her 

 labors. Her body which was at first plump, swollen and un- 

 wieldy, is now shrunken and flaccid, and she is so exhausted 

 that she soon lets go her foothold, falls to the ground and per- 

 ishes. The designs of nature in giving to these insects the 

 habits which they possess are very evident. Having no wings by 

 which to escape when menaced with danger, were these worm- 

 like females to crawl about 'the limbs and trunk of the tree, as 

 the canker worms are accustomed to do, their pale gray bodies 

 would cause them to be discovered and devoured by birds. The 

 canker worm runs no risk of this kind, as it makes its ascent in the 

 winter and early spring when the birds are all absent upon their 

 migration to a warmer climate. The vaporer moth, coming out 

 in August, by remaining stationary upon its light colored cocoon, 

 is but little liable to be noticed. Still, there being even here 

 some risk of its discovery, it hastens to fulfill the purpose of 

 its existence immediately upon coming out of its cocoon, lest 

 some mishap should befall it if it were to remain longer in this 

 exposed situation. 



The white frothy matter with which the eggs are covered be- 

 comes dry and hard and impervious to wet, thus protecting them 

 through all the storms and vicissitudes of autumn, winter and 

 spring. Nor will a bird be inclined to pick off and devour these 

 eggs with this foam and the hairs of the cocoon adhering to them. 

 They are thus shielded from harm although placed in such an 

 exposed situation, until the return of warm weather brings out 

 a crop of leaves for the subsistence of the worms; whereupon 

 they hatch from the eggs, early in May, and grow up till they 

 become the gay caterpillars which we first noticed above. 



But though the vaporer moth is able to guard itself and its 

 progeny from destruction in several directions, it is not thus 



