IMPKOVEMENT OV THE HUMAN 13KEED. 



529 



shall I regard the .slight mnnerical inequality of the sexes, but will 

 simply suppose that each parentage produces one couplet of grown-up 

 tilials, an adult man and an adult woman. 



The result is shown to the nearest whole per thousand in the diagram 

 up to " U and above." It may ])e read either as applying to fathers and 

 their sons when adult, or to mothers and their daughters when adult, 

 or, again, to parentages and filial couplets. I wnll not now attempt to 

 explain the details of the calculation to those to whom these methods 

 are new. Those who are familiar with them will easily understand the 



I 

 I 



exact process from what follows. There are three points of reference in 

 a ."Scheme of de-scent, which may be respectiveh' named "mid-parental," 

 "genetic," and "filial" centers. In the present case of both parents 

 being alike, the position of the mid-parental center is identical with that 

 of either parent separately. The position of the filial center is that from 

 which the children di.sperse. The genetic center occupies the same posi- 

 tion in the parental series that the filial center does in the filial series. 

 Natural Inheritance contains abundant proof, both observational and 



SM 1901 34 



