38 



INBREEDING AND OUTBREEDING 



are similar in all essential features, as may be seen in Fig. 

 9, the elimination of three out of four of the oocytes taking 



ODGENISI3 



/^*>, 



. (J$ (Q) Wgonia 



>5^l/ +y 



Pairln * f Chpo osome6 

 Reducing division 



Fio. 9. Diagram of gametogenesis showing the parallel between maturation of the sperm 

 cell and maturation of the ovum. (After Guyer.) 



place in order that their store of nutritive materials may 

 go to make one large egg. 



Fertilization consists in the fusion of one egg with one 

 sperm, thus bringing back the double number of chromo- 



