VIEWS OF LAMARCK 377 



reproduced itself many times, it reaches, by slow degrees, the 

 dry and almost arid soil of a mountainous region ; if the plant 

 succeeds in living there, and perpetuates itself for a succession 

 of generations, it will then become so changed that the botanists 

 who come across it will make of it a distinct species." l 



As Lamarck's views have so frequently been misrepresented it 

 is incumbent upon us to make ourselves thoroughly acquainted 

 with what he really meant by the action of the environment, and 

 on this point, fortunately, he is very precise : 



" Here it becomes necessary for me to explain the meaning 

 which I attach to these expressions : The environment (les 

 circonstanccs) influences the form and organization of animals, or 

 in other words, as it becomes very different it changes, in course 

 of time, the form and organization themselves by proportional 

 modifications. 



" Certainly, if people took these expressions literally they 

 would attribute to me an error ; for, whatever the environment 

 may be, it does not directly effect any modification whatever in 

 the form and organization of animals. 



" But great changes in the environment lead, in the case of 

 animals, to great changes in their requirements (besoins), and 

 such changes in their requirements lead necessarily to actions. 

 Now, if the new requirements become constant or very lasting, 

 the animals then adopt new habits, which are as lasting as the 

 requirements which have called them forth. . . . 



" Now, if a novel environment, having become permanent for 

 a race of animals, has given to these animals new habits, or in 

 other words has led them to new actions which have become 

 habitual, there will have resulted therefrom the use of some 

 particular part [of the body] in preference to some other, and in 

 certain cases the complete disuse of some part which has become 

 useless. 



"None of these statements should be considered as hypo- 

 thetical or as the expression of individual opinion ; they are, on 

 the contrary, truths which need only attention and the observa- 

 tion of facts to render them evident. 



" We shall see immediately, by the citation of known facts 

 which attest it, on the one hand that new requirements having 

 made some part necessary, have really, by a series of efforts, 

 caused this part to arise, and that afterwards its continued 

 employment has little by little strengthened it, developed it, and 

 in the end considerably enlarged it ; on the other hand, we shall 

 see that, in certain cases, the novel environment and new 

 requirements having rendered some part quite useless, the 



1 Op. cit., Tom. I, pp. 62, 63. 



