II.] IMPROBABILITY OP WEISMANNISM. 75 



just the same, and environment is impotent. And it 

 does not matter if we assume, with the Neo- Darwinians, 

 that this effect does not become hereditary until the germ 

 is affected — that is, until two or more generations have 

 lived under the impinging environment — it must never- 

 theless follow that the change must have had a definite 

 beginning in the lifetime of an individual ; for it is im - 

 possible to conceive that a change has its origin in two 

 generations. In other words, the beginning is singular; 

 two generations is plural. And whether the modification 

 is directly visible in the body of the organism, or is an 

 intangible force impressed upon the germ, it is neverthe- 

 less of an environmental character, and was at first ac- 

 quired. If this is not true — that the changed conditions 

 of life exert a direct effect upon the phylogeny of the 

 species — then no variation is possible save that which 

 comes from the recompounding of the original or ances- 

 tral sex -elements; and it would still be a question how 

 these sex -elements acquired their initial divergence. 



The Neo -Darwinians would undoubtedly meet this 

 argument by saying that their hypothesis fully admits 

 the importance of these external influences, the only 

 reservation being that they shall have affected the germ. 

 It is true that this is a common means of escape; but 

 it cannot be gainsaid that the denial of the influence of 

 the external or environmental forces is really the fun- 

 damental difference between them and the Darwinians 

 or Neo-Lamarckians, as the following quotation from 

 Weismann will show: "Our object is to decide' whether 

 changes in the soma (the body, as opposed to the germ- 

 cells) which have been produced by the direct action 

 of external influences, including use and disuse, can 

 be transmitted; whether they can influence the germ- 



