396 NATURAL SCIENCE [June 1898 



always interesting reading, even when one does not agree with him. 

 He can defend his thesis admirably ; and the most destructive 

 arguments that are brought against him seem to turn, in his skilled 

 hand, into supports for his views. I am quite convinced that it 

 would be impossible for me to adduce any evidence on my side to 

 which he would not have some reply to make, and so we might 

 prolong this conflict of opinions indefinitely." 



The disputes which have occurred in the last ten years are 

 surely sufficient evidence of this unsatisfactory condition of affairs. 



To recapitulate. I started with the well-known difficulty that 

 biologists have in coming to anything like a unanimous conclusion 

 on this subject. I then endeavoured to prove that more or less 

 equally plausible, though conflicting, theories could be advanced to 

 explain the facts at present collected, leaving entirely out of the 

 article my own views on heredity, and taking up a neutral position ; 

 lastly, I pointed out that this unsatisfactory state of things might 

 be due to a too indefinite use of various terms and too hasty gene- 

 ralisations, and, therefore, that more precise methods were needed. 

 I do not see that any one of these positions has been affected. 



J. Lionel Tayler. 



The Geotto, Hanworth Road, 

 Hampton-on-Thames. 



