THE LAW OF BIOGENESIS 8 1 



After all of the elaborate changes just outlined 

 have taken place, the sperm can fuse with the egg 

 and fertilization is accomplished. (Fig. 30, oppo- 

 site page 90.) Fertilization is really the union or 

 re-mating of the chromosomes of the egg and 

 sperm into a single body, the nucleus. Thus is 

 formed a nucleus that in its chromatin details is 

 unlike any other nucleus that has ever been formed 

 and is unlike any other that will ever be produced 

 in the future. Individuality has its origin in this 

 union of sperm and egg nuclei. 



There are many differences between human be- 

 ings, both evident and hidden. Size, weight, 

 strength, agility are some of these variations that 

 at once occur to the reader but the analysis may 

 well be carried to the more minute differences in 

 our sense organs, our reaction time to stimuli and 

 the quality of our several physiological activities. 

 These numerous differences are all determined 

 when the male and female chromosomes unite in 

 fertilization. So far as adult man is concerned, 

 they are then already formed and fixed. They 

 constitute his equipment and are subject to but 

 slight modification by the processes of education. 



The general statements just made, apply to man 

 and to all animals and plants that reproduce sexu- 

 ally, which is the usual method. After the sperm 

 has merged its identity with that of the egg, an 

 embryo is produced that is capable of developing. 

 There is no specific time when life is added to this 



