, HEREDITY AND SEX 



quickly made good, for delay, if prolonged, would 

 increase the chances of death. 



But i here is another method of division that is almost 

 universal and is utilized by high and by low forms alike : 

 individual cells, as eggs, are set free from the rest of 

 the body. Since they represent so small a part of the 

 body,an immense number of them may be produced on 

 the chance thai a few will escape the dangers of the 

 long road leading to maturity. Sometimes the eggs 

 are protected by jelly, or by shells, or by being trans- 

 parent, or by being hidden in the ground or under 



lies, or even in the body of the parent. Under these 

 circumstances the animal ventures to produce eggs with 

 ;i large amounl of food stored up for the young embryo. 



- far reaching were the benefits of reproduction 

 by eggs that it has been followed by almost every 

 species in the animal and plant kingdom. It is ad- 

 hered t<. even in those cases where the animals follow 

 other grosser methods of separation at the same time. 

 We find, however, a strange limitation has been put 

 upon the process of reproduction by eggs. Before the 



_ begins its development it must be fertilized. Cells 

 from two individuals must come together to produce 

 a new one. 



The meaning of this process has baffled biologists 

 ever since the changes that take place during fertili- 

 Bation were firsl discovered; in fact, long before the 

 actual processes that take place were in the least un- 

 derstood. There is a rather extensive and antiquated 

 literature dealing with the part of the male and of 

 the female in the process of . procreation. It would 

 take us too far to attempt to deal with these questions 



