Form and Color in Nature. 245 



animal and vegetable life, showed in great detail the amount 

 of variation which is constantly occurring, and therefrom 

 conclusively proved the inevitableness of natural selection 

 and the survival of the fittest as an important controlling 

 factor in the development of species. He never, however, 

 contended that this was the sole factor, and, with the free- 

 dom from bias which always characterized him, during his 

 later years he was disposed to grant more importance to use 

 and to sexual selection than he had formerly been ready to 

 allow. Wallace, his co-discoverer of the principle of natural 

 selection, has not been disposed to accompany him in his 

 later conclusions, and in his " Darwinism," printed last year, 

 he reiterates and argues at great length for his thesis that 

 natural selection has been the principal, and practically the 

 sole, cause of development. I think, however, that it is im- 

 possible to read his work without being impressed with the 

 strength of his bias, and to me the alteration of his attitude 

 when he comes to treat of mental phenomena and of man 

 is almost ludicrous. I can not think of it as otherwise than 

 strikingly inconsistent. 



Those of you who heard Prof. Cope's lecture in this place 

 a few mouths ago will remember into what detail he entered 

 in confutation of Mr. Wallace. Mr. Cope is perhaps dis- 

 posed to go further even than Darwin in the direction of 

 Lamarck. Herr Eimer also is a neo-Lamarckian, laying 

 great stress upon the effect of use and habit and upon the 

 inheritance of acquired characters. He has done a most 

 useful work in the accumulation of evidence upon the lat- 

 ter point, and among this evidence there is not a little of 

 seeming incontrovertibility touching the inheritance even 

 of physical mutilations, such as the loss of a finger or a scar 

 upon some particular part of the person, as well as of a tend- 

 ency to certain diseases. 



Eimer contends that there is a principle of growth or 

 development in organic nature which corresponds with the 

 inorganic tendency to a certain form of crystallization, and 

 that natural selection acts upon the variations thus pro- 

 duced and sifts out those which are to endure. I can not 

 discover anything so heinous in this theory; on the con- 

 trary, it seems to me most consonant with that which we 

 see m other fields, of an all-controlling law or living pres- 

 ence, a persisting force which produces results through an 

 intricate system of checks and balances. 



Herr Weissman, on the contrary, whom Wallace quotes 



