THE CATERPILLAR. C3 



wrap themselves up. Many are the forms which 

 these animals assume in this helpless state ; and 

 it often happens, that the most deformed butter- 

 flies issue from the most beautiful aurelias. 



In general, however, the aurelia takes the rude 

 outline of the parts of the animal which is con- 

 tained within it; but as to the various colours 

 which it is seen to assume, they are rather the 

 effect of accident ; for the same species of insect 

 does not at all times assume the same hue when 

 it becomes an aurelia. In some, the beautiful 

 gold colour is at one time found ; in others it is 

 wanting. This brilliant hue, which does not fall 

 short of the best gilding, is formed in the same 

 manner in which we see leather obtain a gold 

 colour, though none of that metal ever enters 

 into the tincture. It is only formed by a beauti- 

 ful brown varnish, laid upon a white ground ; 

 and the white thus gleaming through the trans- 

 parency of the brown, gives a charming golden 

 yellow. These two colours are found, one over 

 the other, in the aurelia of the little animal we 

 are describing ; and the whole appears gilded, 

 without any real gilding. 



The aurelia thus formed, and left to time to 

 expand into a butterfly, in some measure resem- 

 bles an animal in an egg, that is to wait for ex- 

 ternal warmth to hatch it into life and vigour. 

 As the quantity of moisture that is enclosed 

 within the covering of the aurelia, continues to 

 keep its body in the most tender state, so it is 

 requisite that this humidity should be dried 

 away, before the little butterfly can burst its 



