170 INSECT TRANSFORMATIONS. 



like a worn shirt; and the caterpillar appears in an 

 entire new dress, the tints of which are fresher and 

 brighter, and the colours and markings often con- 

 siderably different from the former. The insect, 

 also, in consequence of the quantity of fat which has 

 gone to augment its several parts, becomes all at 

 once so much enlarged in size, that we can with diffi- 

 culty conceive how it could have been contained in 

 the old skin, out of which it has just crept. The 

 cast skin is frequently so very perfect that it might 

 almost be supposed to be the caterpillar itself, particu- 

 larly in those which are hairy, as this contributes to 

 conceal the shrivelling. 



That the above account of the process of casting the 

 skin is correct, appears both from the careful dissections 

 which have been made by Swammerdam, Lyonnet, 

 and Ramdohr, and also from the diseases incident 

 to caterpillars from deficiency of food or of pure air. 

 It is a circumstance of common occurrence to those 

 who are in the habit of breeding insects, that when 

 they are not supplied with a sufficient quantity of 

 food, their bodies do not increase enough in thick- 

 ness to rupture the old skin; yet this becomes in due 

 time hard and shrivelled from the absorption of the 

 fat, though the insect, frjm its inability to break 

 through, remains imprisoned. It might be sup- 

 posed, that if plenty of food were at this moment 

 suppHed, it would subsequently acquire sufficient bulk 

 and strength to rupture and escape from the old skin; 

 but this is impossible, as we have repeatedly found 

 to our great disappointment. In the instance of 

 the caterpillar of the moth, called by collectors the 

 glory ©f Kent {Endromis versicolora, Stephens), 

 which we found on a lime-tree at Lee, and were 

 anxious to rear, fresh food was neglected to be 

 given to it a short time before its third moult; and 

 from that time it refused to eat, and soon died. By 



