MENDELIAN SEGREGATION 



23 



The two pairs of chromosomes ^^ assort^' on the 

 spindle in either one of the two ways shown in the 

 diagram; resulting in four and only four kinds of 

 gametes. 



EGGS 



SPERM 



c 



LONG 



GRAY 



c 



dUD 



LONG 



CRAY 



D 



C 



anmiE) 



LONG GRAY 



anmiD) 



LONG CRAY 



c ■) 



LONG 



GRAY 



LONG 



EBONY 



anmnD 



LONG GRAY 



jnTTTTTD 



LONG EBONY 



anmni) 



C 



LONG 



GRAY 



dnnniDi 



LONG 



GRAY 



annniD 

 (nmniD 



VESTIGIAL GRAY 



amnni) 

 dnnmi) 



VESTIGIiL GRAY 



ammiD 



c 



LONG 



3 



GRAY 



(tannip 



LONG 



EBONY 



mm 



VESTIGIAL GRAY 





VESTIGIAL EBONY 



Fig. 12. — Diagram to show the 16 possible kinds of permutations of 

 the four kinds of gametes of Fig. 11. Along the top line are four kinds 

 of eggs; along the left side are four kinds of sperm; in the squares are the 

 combinations formed by the meeting of each kind of egg with each kind 

 of sperm, giving 9 long gray; 3 long ebony; 3 vestigial gray; 1 vestigial 

 ebony. 



The process just described takes place both in the 

 male and in the female. Consequently there will 

 be four kinds of eggs and four kinds of spermatozoa. 



