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The Beginning and End of Life 403 



increased task is placed upon natural selection. On this 

 account he also denies that favourable variations can occur in 

 parthenogenetic reproduction, or at least that it can be more 

 than minute and insignificant when compared with the effects 

 of ordinary reproduction. The Professor says (p. 275) : ' If it 

 could be shown that a purely parthenogenetic species had 

 become transformed into a new one, such an observation 

 would prove the existence of some force of transformation 

 other than selective processes, for the new species could not 

 have been produced by the latter.' But we have the authority 

 of Professor Sydney H. Vines for affirming that new species 

 have appeared .m. parthenogenetic plants, and the same 

 thing appears certainly to have occurred amongst the par- 

 thenogetic wheel-animalcules. But not only, according to 

 Professor Weismann, are such forms unable to evolve new 

 species, they are also unlikely to have themselves a long 

 existence. But amongst the Fungi, a number of genera and 

 species are admittedly parthenogenetic, and yet these plants 

 exhibit not the slightest tendency to die out. These fungi, 

 such as our common mushroom, fairy rings, etc., ' 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.' ^ Professor Vines may well ask how, on 

 Professor Weismann's hypothesis, can all the variations and 

 evolutions of new forms which have taken place in this 

 group of organisms be accounted for? It appears to us to 

 be a second absolutely fatal objection — that concerning the 

 two polar bodies in the drone's Q,gg being the first such. 



But if the Weismann theory renders the evolution of new 

 parthenogenetic species impossible, it appears to us to make 

 the evolution of -^lOTi-parthenogenetic species impossible also. 



1 Nature, Oct. 24th, 1889, p. 626. 



