Weismannism up to date (1893). 155 



emphasized that, as Professor Hartog has observed, 

 no one of his reviewers has noticed it 1 . In the 

 second place, he nowhere expressly recognizes the 

 effects upon his theory of evolution, which necessarily 

 follow from the change. And, lastly, the manner in 

 which he endeavours to underpin that theory after 

 having thus removed its logical foundation in his 

 former postulate of the absolute stability of germ- 

 plasm, is so peculiar that it is hard to epitomize his 

 reasoning with due regard to brevity. 



Speaking for myself, I can only say that my first 

 impulse, after reading the sentences above quoted, 

 was to cancel the whole of Chapter IV, as well as all 

 those parts of Chapters I and III where the Weis- 

 mannian theory of evolution is alluded to ; and then 

 to start anew with a bare statement that this theory 

 had now been wholly discarded by its author. But 

 after due consideration it seemed desirable to leave 

 the criticism as it was originally written, not only on 

 account of the reasons already stated in the Preface, 

 but still more because I found it would be impractic- 

 able to start a new criticism of the greatly modified 

 theory of evolution without introducing many and 



1 Nature, May u, pp. 28-29. — In 1891-2 Professor Hartog furnished 

 a criticism of Weismann's theory of Heredity {Nature, vol. 44. p. 613, 

 and Contemporary Review, July, 1892^. Although disputed at the time 

 by some of Weismann's followers in England, this criticism was one of 

 unquestionable cogency, and has now been recognized as such by 

 Weismann himself {The Germ-plasm, pp. 434-5). The main point of 

 the criticism had been missed by previous critics of Weismann, and 

 consisted in revealing an important " difficulty " inherent in the structure 

 of the theory itself. How far this criticism had the effect of causing 

 Professor Weismann to abandon his theory of variation being ex- 

 clusively due to amphimixis, as Professor Hartog appears to think 

 {Nature, May 11, 1893, p. 28), is immaterial. But it must be observed 

 that as far back as February, 1890, Professor Weismann in his answer to 

 Professor Vines' criticism wrote the passage already quoted on page 152. 



