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 



dmnnDi 



LOMG GRAY 



IfflMDl 



LONG CRAY 



dfflniiD 



LONG GRAY 



amnni) 



LONG EBONY 



annmi) 



must' c 3 

 dinniiD c 3 



VESTIGIttL GRAY 



dnnnn) 

 anmnp 



VESTIGIAL GRAY 



arnmiDi 



annmi' 



JTMTTt ) 



(fflnmr) 



VESTIGIAL GRAY 



(fflfflmx 



JTTTmTDi 



VESTIGIAL EBOMY 



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

 the four kinds of gametes of Fig. 11. Along the top line arc 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. Conseciuentl}^ there will 

 be four kinds of eggs and four kinds of spermatozoa. 



