176 INBREEDING AND OUTBREEDING 



velop to twice the extent of either parent, because there 

 are present eighteen different factors instead of nine. 



TABLE VII 



COMPOSITION OF A MENDELIAN TRI-HYBRID IN F WHERE THE DEVELOPMENT 

 WHICH EACH INDIVIDUAL ATTAINS DEPENDS UPON THE NUMBER OP 

 HETEROZYGOUS CHROMOSOMES CONTAINED AND THEREBY UPON THE 

 TOTAL NUMBER OF DIFFERENT FACTORS PRESENT. 



Distribution of the Fj individuals according to the development attained 



Classes 



Frequency. 



8 

 24 



10 

 24 



12 = 4 



8 =64 



Number of classes 

 Total population 



Following this hypothetical case into the second gen- 

 eration by selfing or by interbreeding the individuals of 



