io6 Heredity and Social Progress 



has an enclosed ovary which in its develop- 

 ment becomes a head, and an exposed or out- 

 side ovary which takes part in reproduction. 

 The head of a female would be male, while 

 the head of a male is female. This origin 

 of the head demands no other elements than 

 those known to exist in the simpler phenomena 

 of cell life. 



There is an even less complex hypothesis 

 than this, although it offers fewer analyses to 

 prove it a possible line of development. When, 

 in fertilization, the male element enters the 

 female cell, the two nuclei join into one which 

 may not lose the identity of either. In 

 each the chromosomes have been reduced to 

 half of their normal number, a fact which 

 has been taken to imply that in the union a 

 single nucleus is formed with the proper num- 

 ber of chromosomes, one half coming from the 

 male, and the other from the female. Another 

 interpretation is, however, possible. The reduc- 

 tion in each germ, whereby some of its elements 

 are lost, may have been due to an emotion by 

 which the more specialized parts were thrown 

 off. A regeneration could then make each 



