178 



BREEDING 



of the union of gametes bearing similar character- 

 factors, and is called a homozygote, the adjectival 

 form of which is homozygous : of this there are two 

 kinds, DD and EE. The other kind of zygote is 



(J gametes 

 A a 



a 



Oh 



the result of the union of gametes bearing dissimilar 

 character-factors, and is called a heterozygote, the 

 adjectival form of which is heterozygous : of this 

 there is only one kind, DE. 



The heterozygote may either bear the character 

 of its dominant parent, as in stature in peas; or it 

 may possess a character peculiar to itself and 

 inseparable from the heterozygous condition, as in 

 the case of the Andalusian fowl. In such a case 

 it is useless to attempt to fix the hybrid character. 

 A similar case amongst cattle is red-roan, which is 

 a heterozygote between red and white. 



It now remains to consider the results of the 

 difierent types of matings which may be made 

 between the three types of zygotes, DD, DE, and 

 EE, It is hardly necessary to point out how impor- 



