218 GENERAL BIOLOGY 



decreasing that from more remote ancestors. But 

 it seems to remain true that half or more than half 

 of the individual's inheritance is derived from his 

 immediate parents. 



The sort of characteristics with which Galton 

 worked were such as vary continuously ; for example, 

 stature and other measurable qualities. It is a 

 frequent characteristic of such structures, that they 

 blend or mix in inheritance. The children of tall 

 fathers and short mothers tend, on the average, to 

 be neither tall nor short, but rather intermediate 

 in height. It has been found that this is not at 

 all true of a great many kinds of inherited characters. 

 The eye-color of a child whose mother has blue eyes 

 and his father brown eyes will not be a blend or a 

 mixture of the two colors, but will be like either 

 one parent or the other. (There is an occasional 

 exception.) Again the cross between a white flower 

 and a red flower will frequently be striped red and 

 white. In such cases, it is evident that Galton's 

 law of ancestral inheritance does not apply. It is 

 customary to call the last type particulate inheri- 

 tance, the second type (such as eye-color) alternative 

 inheritance, and the first type, blended inheritance. 

 Whether or not there is any fundamental difference 

 between the three types has not been fully established. 

 Recent breeding experiments with both plants and 

 animals have shown that an unexpectedly large 

 proportion of inheritance is of the alternative type, 

 and a correspondingly small proportion truly blended 

 or particulate. 



