To tbis system may be attributed, in a great measure, tlie 

 rapid progress which Natural History has made since it was 

 promulgated. The first outline appeared in 174B, and was per- 

 fected in the 12th Edition of his Systema JVaturce, published in 

 1766. This system was improved by Blumenbach, in his 

 *' Manual of Comparative Anatomy," published in 1803. 



The modern discoveries, however, by Cuvier, Geoffroy, 

 Lamarck, and other French comparative anatomists, have point- 

 ed out the necessity of substituting other arrangements. Among 

 the various systems which have been devised, that of Cuvier 

 seems to approach nearest to the natural affinities; especially in 

 his class Mammalia, which is that we have adopted, with the 

 addition of some new genera, possessing decided characters. 



Cuvier separates all known animals into /our great divisions : 

 namely, I. Vertebrated animals ; II. Molluscous animals ; 

 III. Articulated animals; and, IV. Radiated animals. 

 The foundation of these divisions rests on the organization of 

 the various animals, as they exist in nature. 



