38 THE FAMILY AND THE NATION 



We therefore get the following theoretical pedi- 

 gree : — 



00 



® 



OR) =^ (RR) 



I 



®=f=® 



® 



(RR) 



r 



1 



® 



1 

 (rr) 



If we wish to trace a dominant character, we may- 

 make its descent more visible in the diagram by repre- 

 senting it as ^ if pure bred, and as ^ if half-bred. 

 Although these two classes are identical in outward 

 appearance, their innate differences show at once in 

 their offspring. We then get the scheme 



o 



o^ 



o 



o 



o^=o 



o 



o 



Here we have traced the descent of a dominant 

 character in a recessive population : the inheritance of 

 a brown-eyed strain in a grey-eyed people. 



Whenever we find a character transmitted in such a 



