250 PLANT HYBRIDIZATION BEFORE MENDEL 



In Tables 19 and 20 (pp. 215-16), the observed and the cal- 

 culated eye-colors are given for 16 groups of families, in which 



". . . those families are grouped together in whom the distribution of 

 light, hazel, and dark eye-colour among the parents and grandparents 

 is alike. Each group contains at least twenty brothers or sisters." (p. 215.) 



The correctness of the calculations, as compared with the ob- 

 served data, are well shown, as Galton remarks, by the totals in 

 Table 19, in which the aggregate calculated number of light-eyed 

 children, under Groups I, II, III, are given as 623, 601, and 614, 

 respectively, while the observed numbers were 629, being correct, 

 therefore, in the ratio of 99, 96, and 98 to 100. 



Galton concludes his observations on the subject of eye-color 

 as follows : 



"My returns are insufficiently numerous and too subject to uncertainty 

 of observation, to make it worth while to submit them to a more rigorous 

 analysis, but the broad conclusion to which the present results irresistibly 

 lead is that the same peculiar hereditary relation, that was shown to 

 subsist between a man and each of his ancestors in respect to the quality 

 of stature, also subsists in respect to that of eye-colour." (p. 153.) 



No attempt will be made to discuss the data and calculations 

 with respect to inheritance of artistic faculty and of disease. 



Sufficient has been presented to show the mode of operation of 

 Galton's mind in respect to the matter of inheritance. It suffices 

 to say, that Galton's work constituted the first considerable at- 

 tempt at an exact analysis of hereditary data upon a mathe- 

 matical basis, during the pre-Mendelian period. The fact that his 

 data do not constitute a genetic analysis, but a statistical state- 

 ment of the general result in respect to populations, does not de- 

 tract from their absolute value, or from their correctness from the 

 standpoint of the operation of the law of averages upon popu- 

 lations, where the data for several generations are properly 

 grouped and classified as a whole. 



In 1897 (2b) Galton contributed to the Proceedings of the 

 Royal Society (Vol. 61, pp. 401-13, June 3, 1897), a brief memoir 

 constituting the continuation of his investigation upon the law of 

 ancestral inheritance reported in his "Natural Inheritance" of 

 1869, the material from which the memoir was derived being 

 the pedigree records of the well-known Basset hounds of Sir 

 Everett Millais. The paper in question is entitled, "The average 



