THE TRANSMUTATION OF SPECIES. 257 



generality of mankind, as real, because in general our 

 judgment is only relative to ourselves.' Our notion of 

 the permanence of 'species' is based, therefore, upon 

 our idea of the stability of the conditions existing in 

 each area; since species remain unchanged so long as 

 their environment remains the same, and the latter 

 changes so slowly as to elude our powers of observa- 

 tion. 



Lamarck's doctrine that useful structures in animals 

 are really the result of the actions of surrounding 

 conditions, has been interpreted as implying that such 

 structures could be developed by repeated acts of volition 

 on the part of an animal. This, however, is a travesty 

 of his actual views,* and arises from confounding the 

 requirements ('besoins') of an animal, and the actions 

 thence resulting, with its wishes. As a good deal of 

 misconception has prevailed upon this point, it may be 

 well to quote one of the passages in which Lamarck 

 expresses his views in a concrete form : 



'I propose to show,' he remarks, 'that the continued 

 use of an organ, together with the eiforts made by the 

 animal to adapt the organ for the purposes which its 

 surroundings render necessary, will strengthen, develop, 

 and enlarge that organ, or will create new organs which 

 are capable of discharging the functions which have 

 become needful. 



'The bird which necessity conducts to the water for 

 the purpose of obtaining its food, separates its toes when 

 it wishes to strike the water or move upon its surface. 



* This has been lately insisted upon by Professor P. Martin Duncan, in the 

 anniversary address to the Linnean Society for 1884, in which an excellent 

 summary of Lamarck's philosophico-zoological views is given. 



Q 



