36 Amphimixis as a mingling 



view, been absolutely inoperative beyond it. 

 Natural selection and the blending of an- 

 cestral traits, more or less diverse, have 

 henceforth sufficed. 



The essentials of this process of amphi- 

 gony or mixed generation, as Weismann 

 conceived it, are simple enough. Two packs 

 of shuffled cards he has himself suggested 

 as representing the paternal and maternal 

 germ-plasm. Now imagine half of each 

 rejected and a new pack made of the re- 

 mainders. A portion of this new pack will 

 remain unaltered, though it will grow in- 

 definitely: this portion is the latent germ- 

 plasm that continues undeveloped until 

 the advent of a new generation, when the 

 processes of mixing, shuffling, and reducing 

 division are repeated. From the remaining 

 portion the new individual arises. Any one 

 of the cards would suffice for its complete 



