90 An Examination of Weismannism. 



sufficiently extensive observation, the fact would 

 become one of immense significance— so much so, 

 indeed, that of itself it would go far to neutralize all 

 antecedent objections, and to verify his theory as to 

 sexual propagation being the sole cause of congenital 

 variation. But seeing that the alleged fact stands so 

 entirely out of analogy with the phenomena of bud- 

 variation (which will be alluded to later on), it is 

 highly improbable, even on antecedent grounds ; while 

 Professor Vines has refuted the statement on grounds 

 of actual fact. Thus, speaking of the Basidiomycetes, 

 he says — 



These Fungi are not only entirely a-sexual, but it would appear 

 that they have been evolved in a purely a-sexual manner from 

 a-sexual ascomycetous or ascidiomycetous ancestors. The 

 Basidiomycetes, in fact, afford an example of a vast family of 

 plants, of the most varied form and habit, including hundreds 

 of genera and species, in which, so far as minute and long- 

 continued investigation has shown, there is not, and probably 

 never has been, any trace of a sexual process l . 



Here, then, we have actual proof of "hereditary 

 individual variations v among a-sexually propagating 

 organisms, sufficient in amount to have given origin, 

 not merely to " individual differences." but to in- 

 numerable species, and even genera. Consequently 

 Weismann allows that the criticism abolishes this line 

 of evidence in favour of the absolute stability of germ- 

 plasm 2 . Consquently, also, we must now add, in 

 whatever measure the alleged fact would have corro- 

 borated the theory had it been proved to be a fact, 

 in that measure is the theory discredited by proof that 



1 Nature, voL xl. p. 626. 



1 Ibid., vol. xli. p. 32a. 



