BARON CUVIER. 107 



exist in nature four principal forms, or general 

 plans, according to which all animals seem to 

 have been modelled, and the ulterior divisions of 

 which, whatever name the naturahst may apply 

 to them, are but comparatively slight modifica- 

 tions, founded on the developement, or addition 

 of certain parts, which do not change the es- 

 sence of the plan." The introduction to these 

 volumes contains the definition of classes, orders, 

 genera, &c., a general view of that which is 

 called organisation, particularly that of animals, 

 its chemical composition, its forces, its intel- 

 lectual and physical functions, and the applica- 

 tion of method to the four great forms of the 

 animal kingdom. From the latter I must be 

 allowed to make a short extract. " In the first 

 (form), which is that of man, and the animals 

 which most resemble him, the brain and the 

 principal trunk of the nervous system are en- 

 closed in a bony envelope, which is composed of 

 the skull and vertebrae : to the sides of this mid- 

 dle column are attached the ribs and bones of 

 the limbs ; all of which form the frame-work of 

 the body. The muscles which give action to 

 these bones generally cover them, and the vis- 

 cera are contained in the head, and the trunk, 

 or body. These are styled vertebrated animals : 



