Characters, Hereditary and Acquired. 143 



published a word upon the subject. But it now 

 seems worth while to do so, and for the following 

 reasons. 



First, as just observed, a brief account of my old 

 experiences in this field will serve to show what good 

 reason I have for feeling the weight of such negative 

 evidence in favour of Continuity as arises from failure 

 to produce any good experimental evidence to the 

 contrary. In the second place, now that the question 

 has become one of world-wide interest, it would seem 

 that even negative results deserve to be published 

 for whatever they may be worth on the side of Neo- 

 Darwinism. Lastly, in the third place, although the 

 research yielded negative results in my hands, it is 

 perhaps not undesirable to state the nature of it, 

 if only to furnish suggestions to other physiologists, 

 in whose hands the experiments — especially in these 

 days of antiseptics — may lead to a different termina- 

 tion. Altogether I made thousands of experiments 

 in graft-hydridization (comprising bines, bulbs of 

 various kinds, buds, and tubers) ; but with uniformly 

 negative results. With animals I tried a number of 

 experiments in grafting characteristic congenital tissues 

 from one variety on another — such as the combs of 

 Spanish cocks upon the heads of Hamburgs ; also, 

 in mice and rats, the grafting together of different 

 varieties ; and, in rabbits and bitches, the transplant- 

 ation of ovaries of newly-born individuals belonging 

 to different well-marked breeds. This latter experi- 

 ment seems to be one which, if successfully performed 

 (so that the transplanted ovaries would form their 

 attachment in a young bitch puppy and subsequently 

 yield progeny to a dog of the same breed as herself) 



