LAWS OF GALTON AND MENDEL 183 



The hybrid gives rise to two categories of germ cells, 

 equal in numbers and representing potentially the 

 two contending characters, which accounts for the 

 segregation of characters. Correns, rejecting Men- 

 del's explanation, supposes that the segregation orig- 

 inates in the cleavage which occurs at the time of 

 maturity. 



Whatever the cause of segregation may be, the very 

 fact of segregation harmonises with the modern the- 

 ories of representative particles; it supplies new evi- 

 dence in support of Weismann's theories of develop- 

 ment and heredity. 



The Mendelian discoveries have also an important 

 bearing upon the question of natural selection, espe- 

 cially as one of the antiselectionist arguments is based 

 upon the statement that the effects of selection disap- 

 pear in the course of several generations, particularly 

 in cases of cross-fertilisation. The observations made 

 by Mendel and other scientists prove that characters 

 can perpetuate themselves without suffering any at- 

 tenuation, and therefore the argument based on Gal- 

 ton's law collapses entirely. The Neo-Darwinians 

 draw from Mendel's observations the same conclusion 

 as to the persistence of characters. 



In the third place the fact that new characters ap- 

 pear per saltum, and not through the accumulation of 

 what Darwin calls slight variations, constitutes an ar- 



