20 AMPHIMIXIS. 



The embryo of both sexes fundamentally alike, but 

 the germ cell develops in one of two ways, according 

 to unknown and doubtless varying stimuli. Without 

 a stimulus each nucleus is sexless. ( Wdtase.) 



Fertilization not a rejuvenation, but a mixing of 

 characters. Each new individual would be a "branch 

 or elongation of the parent " (Erasmus Darwin), except 

 for amphimixis. 



Inherited dependence prevents ordinary cells from 

 acting as germ cells in higher animals. Growth by 

 budding or fusion in lower animals or plants. 



Inherited dependence prevents parthenogenesis in 

 any of the higher forms of life. 



" Nature has no better way of encouraging varia- 

 tion than by preventing individual germ cells from 

 developing alone." 



" Whatever is desirable in Nature becomes necessary 

 as soon as it is possible."-- Weismann. 



The infinitely little shown in units of heredity. The 

 question of size a relative one ; on either side extends 

 infinity. 



