Phenomena of Inheritance 



in 



FIG. 35. BLENDING INHERITANCE OF SIZE IN RABBITS. The skulls of two 

 parents are shown in I and 3, of their intermediate offspring in 2. (From 

 Castle.) 





brids, trihybrids or polyhybrids. As a result offspring appear 

 more or less intermediate in size between their parents. 



Thus it is possible to explain even "blending" inheritance as 

 due not to the real fusion or blending of inheritance factors but 

 to varying combinations of numerous or multiple factors, accord- 

 ing to the Mendelian rules. The Mendelian principle of segrega- 

 tion has been found to be of such general occurrence that there 

 is a strong probability that it is universal, and that all cases of 

 "blending" inheritance are due to incomplete dominance or to 

 multiple factors. 



Maternal Inheritance. Another case which seems at first 

 sight to be non-Mendelian is what may be called "maternal in- 

 heritance" since certain characters are invariably derived from the 

 mother and not from the father. Among these are the polarity, 



