150 NATURAL INHERITANCE. [chap. 



of the total number of children in the family will 

 probably possess it. Also, as a consequence of this 

 view of the meaning of a fractional chance, it follows 

 that the residue of 0"40 must be rateably assigned 

 between light and dark Eye-colour, in the proportion 

 in which those Eye-colours are found in the race 

 generally, and this was seen to be (see Table 16) as 

 61'2 :26'1 ; so I allot 0"2& out of the above residue 

 of 0*40 to the heritage of light, and 0*12 to the heritage 

 of dark. When the parent is hazel-eyed I allot -§ of 

 his total contribution of 0'30, i.e., - 20 to light, and 

 -g-, i.e. 0*10 to dark. These chances are entered in the 

 .first pair of columns headed I. in Table 17. 



The pair of columns headed I. in Table 18 shows 

 the way of summing the chances that are given in the 

 columns that have a similar heading in Table 17. By 

 the method there shown, I calculated all the entries 

 that appear in the columns with the heading I. in Tables 

 19 and 20. 



II. Eye-colours given of the four Grand Parents — 

 Suppose D to be possessed by G 1 and that nothing 

 whatever is known with certainty of any other ancestor 

 of S. Then it has been shown that the child of G 1 

 (that is F) will possess ^D ; that each of the two parents 

 of G x (who stand in the relation of G 2 to S) will also 

 possess -g-D ; that each of the four grandparents of G x 

 (who stand in the relation of G 3 to S) will possess J-D, 

 and so on. Also it has been shown that the shares 

 of their several peculiarities that will on the average 

 be transmitted by F, G l3 G 2 , &c, are J, ^, ^ ¥ , &c, 



