THE HEREDITY OF RICHARD ROE. 121 



Within the narrowest type there is room for an almost 

 infinite play in the minor variations. For almost any 

 possible one of these, Richard Roe could find warrant 

 in his ancestry. His combination of them must be his 

 own. That is his individuality. Colour of the eyes and 

 hair, length of nose, hue of skin, form of ears, size of 

 hands, character of thumb prints, in all these and ten 

 thousand other particulars some allotment must fall to 

 Richard Roe. 



He must have some combination of his own, for 

 Nature has "broken the die " in moulding each of his 

 ancestors, and will tolerate no servile copy of any of 

 her works. By the law of sex, Richard Roe has twice 

 as many ancestors as his father or mother had. There- 

 fore these could give him anything they had severally 

 received from their own parents. The hereditary gifts 

 must be divided in some way, else Richard Roe would 

 be speedily overborne by them. Furthermore, any 

 system of division Nature may adopt could only be on 

 the average an equal division. Richard Roe's father 

 might supply half his endowment of inborn characters, 

 his mother furnishing the other half. Nature tries to 

 arrange for some partition like this. But she can never 

 divide evenly, and some qualities will not bear division. 

 Richard Roe's share forms a sort of mosaic, made partly 

 of unchanged characters standing side by side in new 

 combinations, partly a mixture of characters, and part 

 of characters in perfect blending. 



The physical reason for all this the physiologists are 

 just beginning to trace. The machinery of division and 



integration they find in the germ cell 

 The germ cell. . * J 



itself the egg and its male cognate. 



At the same time they find that Nature's love of varia- 

 tion is operative even here. She has never yet made 

 two eggs or two sperm cells exactly alike. 



