88 EVOLUTION 



of life. For although the individual A dis- 

 appears in giving rise to B and C, its daughter- 

 cells, we can hardly speak of death when there 

 is nothing left to bury. On the one hand, we 

 reach the idea that death was the price paid 

 for a body; on the other hand, we see that in 

 the simplest forms of life immortality has not 

 even yet been pawned for love. 



THE OEIGIN OF SEX. In many of the uni- 

 cellular organisms there is a kind of sexual 

 reproduction, in the sense that two cells fuse 

 to become one, just as ovum and spermatozoon 

 do in higher creatures. In many cases, more- 

 over, the two cells which fuse are dimorphic, 

 as is well illustrated in the bell-animalcule, 

 Vorticella, where a small, active, free-swim- 

 ming (we may say, male) cell unites with a 

 fixed individual of full size, which may be 

 called female. This is one line of approach 

 to the origin of sex, and it may be noted that 

 the male and female cells illustrate the anti- 

 thesis we have already discussed between 

 relatively more anabolic and relatively more 

 katabolic types. 



The next stage in the problem is to account 

 for the familiar fact that in almost all organisms 

 with bodies there are special reproductive 

 cells, or germ-cells ova and spermatozoa 

 quite distinct from the ordinary body-cells. 



