STATES OF INSECTS. 55 



this subject you cannot do better than consult what the 

 learned Dr. Barclay has said in his admirable work On 

 Life and Organization*, in which he has placed the 

 inanity, the vox et 'prcBterea nihil, of such high-sounding 

 terms in their true light. The processes of nature in 

 the formation and development of the^a^s in utero, of 

 the chick in the egg, of the butterfly in the caterpillar, 

 we in vain attempt fully to investigate ; yet we can easily 

 comprehend that pre-existent germes, by the constant 

 accretion of new matter in a proper state, may be gra- 

 dually developed, but we find it impossible to conceive 

 how, by the action of second causes, without the inter- 

 vention of the first cause, the butterfly should be formed 

 in the caterpillar, unless it preexists there as a germe or 

 foetus. " Is it not clear," asks Dr. Virey in his lively 

 manner, " as Blumenbach and other Physiologists main- 

 tain, that there is a formative power, a nisas formativus, 

 which organizes the embryo ? Admirable discovery ! " 

 says he, " which teaches us that the foetus forms itself 

 because it forms itself ! As if you should affirm that the 

 stone falls because it falls b ! " Had Dr. Herold considered 

 what Bonnet says with as much good sense as modesty, 

 he would never have imagined that his discovering the 

 organs of the butterfly one after the other at certain pe- 

 riods in the caterpillar, was any sound argument against 

 their preexistence and coexistence as germes. " Or- 

 gans," says that amiable and excellent Physiologist, 

 " that have no existence as to us, exist as they respect 

 the embryo, and perform their essential functions ; the 

 term of their becoming visible is that which has been 



* <$ x iv. b N. Diet. d'Hist. Nat. x. 193. 



