NOTE 



The two preceding essays give an account of researches 

 and speculations whicli have a historical value for the 

 philosophic biologist. In both of these articles the 

 reader will find evidence of a belief on my part in 

 " the transmission by heredity of acquired characters." 

 This belief is one which I now think is not justifiable. 

 Some of the questions connected both with Partheno- 

 genesis and Heredity have been elucidated in a masterly 

 manner by August Weismann of Freiburg, whose 

 essays recently published by the Oxford University 

 Press cannot be too carefully studied by naturalists. 



15th March 1890. 



