CHAP, xvin A "FAIRY TALE OF SCIENCE"? 249 



Weismann, because at one time he says that the 

 origin of sex was due to natural selection, at another 

 time that it could not be. In Weismann's system, 

 natural selection works upon the materials furnished 

 to it by sexual reproduction upon the new varieties 

 thus invented upon the new permutations or com- 

 binations of germ plasm, thus manifested, and brought 

 up for judgment in the form of offspring. Still, I see 

 no reason why natural selection should not sit in 

 judgment upon sex itself, if sex somehow originated. 

 No doubt the admission must then be made that 

 Weismann's clear theory of variation had ceased to 

 be available. Sex explains other variations ; what is 

 to explain sex ? It must presumably itself have been 

 a new variation when it appeared for the first time in 

 a sexless world. Once it had appeared, it might 

 well predominate. If some multicellular organisms 

 propagated sexually, and others non-sexually, and if 

 some of the offspring of sexual unions proved supe- 

 rior in the struggle to any of their competitors, why 

 then sex would be selected by nature^ as advanta- 

 geous ; the sexual specimens would tend to be the 

 only ones that survived and reproduced their kind. 

 The origin of sex, accordingly, would still be veiled 

 in deep darkness. Weismann could say little more 

 than that it " happened " to occur. That is very 

 much what he does confine himself to saying "in 

 the present state of our knowledge." Yet it appears 

 perfectly logical to say, not that natural selection 

 brought sex into being ; natural selection originates 

 nothing; it chooses between competing candidates ; 



1 May we say that, upon the whole, it is selected by nature, at least 

 for the higher forms of life ? 



