40 Life and Letters of Francis Galton 



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 of the quality of stature, also subsists in respect to that of 

 eye-colour." (pp. 415-6.) 



The essential fact to be remembered here is that Galton supposes the 

 ancestral contributions which blend in the case of the stature of the indi- 

 vidual, will be found as alternative eye-colours in the same proportions as for 

 stature in the total group of descendants. "For example, if an ancestor 

 contributes 1/pth of his stature deviation to his descendant in the final 

 generation, he will contribute his eye-colour to 1/pth of his descendants in 

 the same generation. 



It would be of great interest to rework Galton's proportions with the 

 actual correlations found from his data, and with the corresponding and con- 

 sistent multiple regression coefficients, and ascertain whether accordance 

 was not sensibly improved. His parental correlation J is too small for his 

 data, and his regression coefficients want considerable modification. 



E. Law of Ancestral Heredity applied to Basset Hounds. Galton 

 having applied his Law of Ancestral Heredity to Eye-Colour in Man sought 

 for additional material to illustrate it. He found this eleven years later in 

 Sir Everett Millais' large pedigree stock of Basset Hounds. This material 

 reached him at the very time he was himself planning an extensive experi- 

 ment with fast breeding small mammals*. One can but regret that that 

 experiment was never undertaken. The Bassets are dwarf bloodhounds, and 

 there are only two varieties of colour, they are either white with blotches 

 from red to yellow technically termed "lemon and white," or they have in 

 addition to this "lemon and white" black markings; in which case they are 

 termed "tricolour." Galton had thus only two types to deal with, which he 

 terms "tricolour" (T)and "non-tricolour" (N). A full report of his statistical 

 reduction of Millais' data is given in a paper read before the Royal Society, 

 June 3, 1897-f. 



Galton's material was contained in The Basset Hound Club Rules and 

 Studbooh, compiled by Everett Millais, 1874-1896, but with this valuable 

 addition, that Sir Everett Millais had added the registered colours of nearly 

 1000 of the hounds (this copy is now in the Galton Laboratory). In this 

 record are 817 hounds, the colour of whose parents are given, and 567 hounds 

 in which the colours of the two parents and the four grandparents are known, 

 and lastly in 188 cases in addition the colour of all the eight great grand- 

 parents. 



Galton starts with the same idea as in the paper last dealt with, namely 

 that each parent contributes £,each grandparent -^ and so on, of the heritage 

 taken as a whole to be unity. Here as in the case of eye-colour, the heritage is 



* An extensive series on moth-breeding had been undertaken but had unfortunately failed 

 to give any satisfactory results, partly owing to the diminishing fertility of successive broods, 

 and partly to the disturbing effects of food differences and change of environment in differentyears. 



t See Roy. Soc. Proc. Vol. i,xi, pp. 401-413. An abstract appeared in Nature, July 8, 1897, 

 Vol. lv, p. 235. 



