RISE AND PROGRESS OF ZOOLOGY. 85 



internal anatomy ? why call in the aid of another 

 science to make that object more perfectly known, 

 which was before sufficiently plain for all the purposes 

 of recognition ? If, as it has been asserted, natural 

 arrangement depends upon internal anatomy, how do 

 we know that it is not equally dependent upon che- 

 mistry ? Has this theory led to the discovery of the 

 natural system ? or to any one of those laws by which 

 such a system may be supposed to be regulated? — 

 Certainly not. The law, as it has been termed, of 

 the condition of existence* ', is no more than that 

 every animal is constructed according to the func- 

 tions it is destined by nature to perform. Now, so 

 far from this, as some have insinuated, being a 

 modern discovery, it was well known to Aristotle ; 

 and is a truth apparent to the most superficial ob- 

 server. It must be admitted, however, that M. Cuvier 

 is the only one of this school who has attached 

 to this theoretic principle of internal organisation 

 so much undue importance: an error he was ob- 

 viously led into from the splendid success which 

 attended its use in his researches on the fossil 

 bones; where, indeed, a complete knowledge of 

 comparative anatomy was absolutely indispensable. 

 It is not maintained that a knowledge of internal 

 anatomy is superfluous to the zoologist ; but that it 

 is quite redundant (and therefore unnecessary), 

 where all that is essential to be known of an animal 

 Can be learned from external organisation. With 

 the exception, therefore, of M. Cuvier, the systems 

 of his celebrated cotemporaries may be said to make 



* Regne Animal. 

 G 3 



