V 



254 FROM THE GREEKS TO DARWIN 



brought forward in support of it. It was such 

 examples as the method of evolution of the snakes 

 that gave Lamarck's critics their opportunity of 

 throwing all his ideas into ridicule; and from 

 some of these brief illustrations his critics spread 

 the impression that he believed animals acquired 

 new organs simply by wishing for them. His 

 really sound speculation in zoology was also in- 

 jured by his earlier and thoroughly worthless 

 speculation in chemistry and other branches of 

 science. Another marked defect was that La- 

 marck was completely carried away with the be- 

 lief that his theory of the transmission of ac- 

 quired characters was adequate to explain all the 

 phenomena. He did not, Hke his contemporaries, 

 Erasmus Darwin and Goethe, perceive and point 

 out that certain problems in the origin of adap- 

 tations were still left wholly untouched and un- 

 solved. Believing that he saw a great evolution 

 factor, and applying it to organic nature, he was 

 blind to its deficiencies and to every other factor, 

 and sought to establish it as a sufficient explana- 

 tion of every change in the animal world. His 

 arguments are, in most cases, not inductive, but 

 deductive, and are frequently found not to sup- 

 port his law, but to postulate it. Another defect 

 was his limited conception of natural environ- 

 ment, in which he was inferior to his contem- 

 porary, Treviranus. Treviranus and St. Hilaire 



