PROGRESS OF ICHTHYOLOGY. 431 



System, are guided by physiological relations, latently in Botany, but 

 conspicuously in Zoology. From the epoch of Cuvier's Rfyne Animal, 

 the progress of Systematic Zoology is inseparably dependent on the 

 progress of Comparative Anatomy. Hence I have placed Cuvier's 

 Classification of animal forms in the next Book, which treats of Phy 

 siology.] 



