FACTORS OF ORGANIC EVOLUTION 47 



factor in organic evolution. It is really this : that, 

 on their master's theory of reproduction, it is 

 impossible to conceive how such transmission can occur. 

 Here I would merely enter a demurrer against this 

 objection, on the grounds that it is unphilosophic. 

 There are countless observed and admitted facts, in 

 all the sciences, which it is as yet impossible to 

 explain. But facts being " chiels that winna ding," 

 they must be accepted nevertheless. Similarly it 

 does not matter one straw whether the Weisman- 

 nians are unable to conceive the manner in which 

 certain facts may be brought about, if they are 

 brought about. When I say it does not matter I 

 do not mean that it is immaterial whether or not 

 the facts are explained ; but that the lack of an 

 explanation cannot for one moment be held to affect 

 or prejudice the fact-ness — if I may coin a word — 

 of any fact. If, then, observation and experiment 

 reveal any instance or instances where, in point of 

 fact, acquired characters are transmitted, the con- 

 troversy must, ipso facto, be regarded as at an end. 

 Such facts, I believe, have been recorded, and else- 

 where I detail them. If this belief be well founded, 

 we are not bound by our further acceptance of 

 Weismann's brilliant theory of the continuity of 

 the germ plasm, to deny that the transmission of 

 acquired characters is, within certain limits and in 

 certain conditions, a factor in organic evolution. 



