252 PLANT HYBRIDIZATION BEFORE MENDEL 



That Galton undertook in a way to conceive of the genotype as 

 the object of his research, is shown by the following statement: 



"It should be noted that nothing in this statistical law contradicts the 

 generally accepted view that the chief, if not the sole, line of descent 

 runs from germ to germ and not from person to person. The person may 

 be accepted on the whole as a fair representative of the germ, and, that 

 being so, the statistical laws which apply to the persons would apply 

 to the germs also, though with less precision in individual cases." 



(p. 403-) 



As an a priori argument for reasonableness of the law, Galton 



says : 



". . . there is such a thing as an average contribution appropriate to 

 each ancestral place, which admits of statistical valuation, however min- 

 ute it may be. It is also well known that the more distant stages of an- 

 cestry contribute considerably less than the nearer ones. Further, it is 

 reasonable to believe that the contributions of parents to children are in 

 the same proportion as those of the grandparents to the parents, of the 

 great-grandparents to the grandparents, and so on ; in short, that their 

 total amount is to be expressed by the sum of the terms in an iafinite 

 geometric series diminishing to zero. Lastly, it is an essential condition 

 that their total amount should be equal to i, in order to account for the 

 whole of the heritage. All these conditions are fulfilled by the series of 

 /^> V2, Vz, etc., and by no other. These and the foregoing considerations 

 were referred to when saying that the law might be inferred with con- 

 siderable assurance a priori : consequently, being found true in the par- 

 ticular case about to be stated, there is good reason to accept the law in 

 a general sense." (p. 403.) 



As to the material of the investigation — the Basset hounds 

 referred to — they were dwarf blood-hounds, showing but two 

 color variations; one white with large blotches ranging between 

 red and yellow, registered as "lemon and white" ; another with 

 the above coloration plus more or less black, called "tricolour." 

 Galton says : 



"Tricolour is, in fact, the introduction of melanism, so I shall treat 

 the colours simply as being 'tricolour' or 'non-tricolour' ; more briefly as 

 T or N. I am assured that transitional cases between T and N are very 

 rare, and that experts would hardly ever disagree about the class to 

 which any particular hound should be assigned." (p. 403.) 



For his purposes, Galton made use of "The Basset Hound Club 

 Rules and Stud Book," compiled by Sir Everett Millais, compris- 

 ing the pedigree records of the hounds in question from 1874 to 

 1896, and containing the names of nearly 1,000 animals. 



Out of these, Galton obtained a series of 817 hounds of knov/n 

 color, descended from parents of known color. In 567 cases out 



