i8o An Examination of Weismannism. 



without any visible medium of communication, the impreg- 

 nated ovum is able to inform the uterus that it is impreg- 

 nated ; and thereupon the uterus behaves towards that 

 ovum in an altogether astonishing manner, such as it never 

 displays towards an unimpregnated ovum. Of course various 

 hypotheses may now be formed to account for this fact, 

 seeing that no one can question it as a fact. But sup- 

 posing that the fact could be questioned, with how much 

 greater effect might it be argued that any communication 

 between the ovum and its soma is even more antecedently 

 incredible when the ovum is entirely free than when it is 

 still contained within its ovary. 



Now these, as far as I can find, are the only grounds 

 for Wei-mann's repeated assertion that the theory of pan- 

 genesis in any form is " inconceivable." I have therefore 

 endeavoured to show that this is too strong a statement. 

 All the facts and considerations whereby he seeks to support 

 it were present to the mind of Darwin ; and, quite apart from 

 any question of relative authority, I cannot avoid agreeing 

 with Darwin that, whether or not the theory is true, at all 

 events the " difficulties" attaching to it on these merely 

 a priori grounds are not insuperable, or such as to render 

 his "pet child" an unconceived monstrosity in logic, or 

 a proved absurdity in science. 



Be it understood, however, that I am not here defending 

 the theory of pangenesis. I am investigating the theory 

 of germ-plasm; and it is because Weismann seeks to 

 sustain the latter by excluding the former as preposterous, 

 that I have been obliged thus to consider the validity of 

 his criticism. For the point to which I am leading is, 

 that Weismann gains nothing in the way of support to 

 his own theory by this disparagement of Darwin's, unless 

 he can show that the former supplies some more " conceivable " 

 explanation touching the mechanism of heredity. Now r I am 

 unable to see that he has shown this. What I do see 



