86 INSECT TRANSF0K3IATI0NS. 



is worthy of remark, that this is the precise form of 

 the arch-stones of a bridge. They are, in fact, built 

 together in the arched form. This, together with 

 the strong cement employed in uniting them, renders 

 it difficult to crush them, though considerable force 

 be used for that purpose; and this even when they 

 are shpped off the branch, round which they are set 

 like pearls on a bracelet, which is the name given 

 them by the French peasantry. The cement, also, is 

 so hard, that when pressed it resists the nail, though 

 it may be pierced with the point of a sharp knife; and 

 not being soluble hi water, ' nor in any other liquid,' 

 says Swammerdam, ' which I have tried,' the heavi- 

 est rain dashes upon the eggs without injury. 



Eggs of the lackey moth, wound spirally round a twig of haw- 

 thorn 5 natural size, and magnified. 



It may be a question with some, when they com- 

 pare these naked eyes of the lackey moth, exposed on 

 a bare branch, with the warm downy covering of those 

 of the gypsey moth, how the former are protected 

 from the colds of winter. This is a question which 

 previous researches cannot fully answer, but one cir- 

 cumstance is obvious — the lackey's eggs are many 

 degrees harder than those of the gypsey, which may 

 be easily crushed. Probably also, this may be con- 

 nected with their electrical state; and that has alwa}s 



