70 METAMORPHOSES. 



might once have furnished arguments for the fictions of 

 the ancients, and the dreams of Paracelsus. We call 

 them metamorphoses and transformations, because these 

 terms are in common use, and are more expressive of the 

 sudden changes that ensue than any new ones. But, 

 strictly, they ought rather to be termed a series of deve- 

 lopments, A caterpillar is not, in fact, a simple but a 

 compound animal, containing within it the germ of the 

 future butterfly, inclosed in what will be the case of the 

 pupa, which is itself included in the three or more skins, 

 one over the other, that will successively cover the larva. 

 As this increases in size these parts expand, present them- 

 selves, and are in turn thrown off, until at length the 

 perfect insect, which had been concealed in this succes- 

 sion of masks, is displayed in its genuine form. That 

 this is the proper explanation of the phenomenon has 

 been satisfactorily proved by Swammerdam, Malpighi, 

 and other anatomists. The first-mentioned illustrious 

 naturalist discovered, by accurate dissections, not only 

 the skins of the larva and of the pupa incased in each 

 other, but within them the very butterfly itself, with its 

 organs indeed in an almost fluid state, but still perfect 

 in all its parts 1 . Of this fact you may convince yourself 

 without Swammerdam' s skill, by plunging into vinegar 

 or spirit of wine a caterpillar about to assume the pupa 

 state, and letting it remain there a few days for the pur- 

 pose of giving consistency to its parts ; or by boiling it 

 in water lor a few minutes. A very rough dissection will 

 then enable you to detect the future butterfly ; and you 

 will find that the wings, rolled up into a sort of cord, are 



* Hill's Swanim, ii, 34. t, 37, f, 2, 4. 



