CHAPTEE VIII 



MENDELIAN INHEBITANCE WITHOUT DOMINANCE, 

 " BLENDING " INHEEITANCE 



WE shall now discuss a seemingly 

 different type of inheritance from 

 that discovered by Mendel, — one 

 in which the offspring are a true intermediate 

 or blend between the parents, and in which the 

 occurrence of segregation has not in all cases 

 been certainly established. 



Differences in size between parents have been 

 found to behave in this blending fashion. Rabbits 

 are apparently favorable material in which to 

 study size inheritance, for some races are fully 

 twice as large as others. If a large rabbit is 

 crossed with a small one the young are of inter- 

 mediate size, and the Fg offspring show no such 

 segregation into large, small, and intermediate 

 individuals as a simple Mendelian system would 

 demand. For this reason size has been de- 



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