232 EXPERIMENTAL EVOLUTION LECT. 



impossible, since the progeny is nothing more than a 

 part of the parent form, an outgrowth thereof, the two 

 being so very similar that in most cases none can tell 

 which is the parent, and which the progeny. It then 

 results if really no selection can occur when sexual 

 reproduction is wanting, and this is a matter which is 

 not settled by Weismann's very sweeping assertion, 

 with which I cannot concur, as there is no reason 

 why some degree of variability should not exist in 

 unicellular organisms as well as among multicel- 

 lular plants or animals that Lamarckian factors 

 must have operated, and must operate even now, if 

 evolution has existed from the beginning, and has 

 been carried on through natural agencies. Weismann 

 strongly argues that at present, at all events, or as 

 concerns higher animals, the Lamarckian factors are 

 possessed of no influence, and his essays on heredity 

 are all against the heredity of acquired characters. 



Such is the present state of the question. I have 

 no intention to discuss the matter, as I have already 

 said ; but I think it may be in the future discussed in 

 a much more profitable manner than has been done till 

 now. And this may be effected through experimental 

 transformism. If we are to subject the evolution 

 theory to the test of experiment, we can only do so by 

 the investigation of the efficiency of the factors of 

 evolution, and we must subject them to the said test. 



