EVOLUTION BEFORE DARWIN 29 



organs, in other words, it is not the nature and shape 

 of the parts of the body of an animal, which determine 

 its habits and its peculiar faculties ; it is on the contrary 

 its habits, its mode of life and the environment in 

 which the individuals from which it is descended 

 lived, which have gradually determined the shape of 

 its body, the number and condition of its organs, and 

 finally its various faculties." 2 



Species are descended one from the other through 

 the hereditary transmission of modifications due to 

 natural causes, apparent to all. Man himself is the 

 result of a transformation of the quadrumana and 

 his mental faculties have no more than those of other 

 animals a superior, supernatural origin. He is sep- 

 arated from them by quantitative, not qualitative, dif- 

 ferences. Here we have the whole theory of evolu- 

 tion with its implied principle of causality applied to 

 all the branches of human knowledge. 



Lamarck's ideas on the mechanism of evolution, 

 that is on the influence of the environment and the 

 use of the organs, were considerably developed in 

 later years, in the nineteenth century and in our days. 

 They gave rise to a whole school of naturalists, the 

 Neo-Lamarckians. 



The idea of transmutation did not meet with any 

 favour during Lamarck's life and did not find ac- 



2 Researches on Living Bodies, p. 50, quoted in Philosophie Zoologique, 

 pp. 237-238. 





