PEOGKESS OF ANIMAL MOEPHOLOGY. 475 



and recognized, and familiarly and successfully applied by botanists 

 And it will be apparent, on reflection, that though symmetry is a no- 

 Lion which applies to inorganic as well as to organic things, and is, in 

 fact, a conception of certain relations of space and position, such de- 

 vdopement and metamorphosis as are here spoken of, are ideas entirely 

 different from any of those to which the physical sciences have led us 

 in our previous survey ; and are, in short, genuine organical or physi- 

 ological ideas ; real elements of the philosophy of life. 



We must, however imperfectly, endeavor to trace the application of 

 this idea in the other great department of the world of life ; we must 

 follow the history of Animal Morphology. 



CHAPTER VII. 

 PROGRESS OF ANIMAL MORPHOLOGY. 



Sect. 1. Rise of Comparative Anatomy. 



most general and constant relations of the form of the organs, 

 *- both in plants and animals, are the most natural grounds of classi- 

 fication. Hence the first scientific classifications of animals are the 

 first steps in animal morphology. At first, a zoology was constructed 

 by arranging animals, as plants were at first arranged, according to 

 their external parts. But in the course of the researches of the anato- 

 mists of the seventeenth century, it was seen that the internal structure 

 of animals offered resemblances and transitions of a far more coherent 

 and philosophical kind, and the Science of Comparative Anatomy rose 

 into favor and importance. Among the main cultivators of this 

 science 1 at the period just mentioned, we find Francis Eedi, of Arezzo ; 

 Guichard-Joseph Duvernay, who was for sixty years Professor of Ana- 

 tomy at the Jardin du Roi at Paris, and during this lapse of time had 

 for his pupils almost all the greatest anatomists of the greater part of 

 the eighteenth century ; Nehemiah Grew, secretary to the Royal So- 

 ciety of London, whose Anatomy of Plants we have already noticed. 

 But Comparative Anatomy, which had been cultivated with ardoi 



1 Cuv. Lermis sur fHist. des Sc. Nat. 414, 420. 



