SUMMARY OF 'PHILOSOPHIE ZOOLOGIQUE: $1 1 



each species has received its habits and corresponding 

 modification of organs, from the influence of the sur- 

 roundings in which it found itself placed.* 



" The first conclusion supposes an unvarying organism 

 and unvarying conditions. The second, which is my 

 theory (la mienne propre), supposes that each animal 

 is capable of modifications which in the course of 

 generations amount to a wide divergence of type. 



"If a single animal can be shown to have varied 

 considerably under domestication, the first conclusion is 

 proved to be inadmissible, and the second to be in con- 

 formity with the laws of nature." 



This is a milder version of Buffon's conclusion (see 

 ante, pp. 90, 91). It is a little grating to read the 

 words " la mienne propre," and to recall no mention of 

 Buffon in the ' Philosophic Zoologique.' 



"Animal forms then are the result of conditions 

 of life and of the habits engendered thereby. With 

 new forms new faculties are developed, and thus nature 

 has little by little evolved the existing differentiations 

 of animal and vegetable life." t 



Lamarck makes no exception in man's favour to the 

 rule of descent with modification. He supposes that a 

 race of quadrumanous apes gradually acquired the 

 upright position in walking, with a corresponding 

 modification of the feet and facial angle. Such a 

 race having become master of all the other animals, 

 spread itself over all parts of the world that suited 

 it. It hunted out the other higher races which were 

 in a condition to dispute with it for enjoyment of the 

 * ' Phil. Zool.,' torn. L p. 263. f Page 265. 



