CUVIER 



Plants, and animals without a circulation, breathe by their 

 whole surface. 



There is accordingly a rational order of functions, and 

 therefore of the systems of organs which perform them. 

 The most important are the Animal Functions, with their 

 great organ-system, the neuro-muscular mechanism. Then 

 come the digestive functions, and after them, and in a sense 

 accessory to them, the functions and organs of circulation 

 and respiration. The last three may be grouped as the 

 Vital Functions. 



The Animal Functions not only determine the character 

 of the Vital Functions, but influence a-lso the primary faculty 

 of generation, for animals' power of movement has rendered 

 their mode of fecundation more simple, has therefore had an 

 effect on their organs of generation. 



This division into " Animal " and " Vital " functions recalls 

 Buffon's and Bichat's distinction of the "animal" and the 

 " vegetative " lives. Cuvier apparently took this idea from 

 1 In (Ton, for he says that a plant is an animal that sleeps. 1 

 But the idea is as old as Aristotle, who discusses the 

 "sleep" of embryos and of plants in the last book of 

 the f>c Gcneratiouc anininlinin. The distinction between 

 animal and -vegetative life is, of course, based for Aristotle 

 in the difference bet\vecn the \^i>x>? aurOijTiKq and the 

 \ f '"X'] OpeTTTiK^. Cuvier, like Aristotle, Buffon, and Bichat, 



makes the heart the centre of the " vegetative " organs. 



It is important to note that Cuvier puts function before 

 structure, and infers from function what the organ will 

 be. " Plants," he writes, " having few faculties, have a very 

 simple organisation." It is only after having discussed and 

 classified functions that Cuvier goes on to examine organs. 



First his views on the composition of the animal body. 

 Ari-totle distinguished three degrees of composition the 

 " elements," the homogeneous parts, and the heterogeneous 

 parts or organs. Cuvier does the same. Some small advance 

 has been made in the two thousand years' interval, due in 

 the first place to the progress of chemistry, and in the second 

 to the invention of the microscope. To the first circum- 

 stance Cuvier owes his knowledge that the inorganic 

 ms d? Anatomic Cf>mp;i>; : ,\ i., p. iS. -' I.oc. <//., i., p. 13. 



