The re-appearance of blue eyes among two of the Scotchman's grandchildren is a clear example of the Mendelian segregation among the gametes of the half-breed Indian mother of the factors which produce blue eyes. The Welsh father, with the hazel eyes, must, of course, as we deduce from other cases, have carried the blue-eye factors recessive.
The black-eyed full blood Indian grandmother also carried various shades of Indian brown, recessive to the Indian black which she herself manifested, since her daughter and two granddaughters exhibited Indian brown and dark Indian brown coloured eyes. The two European brown-eyed grandsons were probably in eye-colour hybrids between the hazel colour of the Welsh father and the Indian brown of the half-breed Indian mother.
The pedigree is thus, in respect of eye-colour—and of other characters also which are not here described—clearly Mendelian in its manifestations. It shows that the offspring of two very different types of human races exhibit the same mode of Mendelian inheritance as do the descendants of two contrasted parents of the same race.
Family 4 (Pedigree Chart, No. K 6) illustrates the same kind of facts and conclusions. In the A Generation a Frenchman, whose eye-colour was unknown to my informant, married a full blood Indian princess who had Indian brown eyes. There was one daughter only (Generation B) by this marriage, and she had Indian brown eyes. She married an Irishman, who had red hair, grey eyes, and a freckled complexion (Generation B). From this marriage there came six children (Generation C). Two of these had "grey eyes like their father." Three had dark brown eyes of European tint. My informant had some doubt as to the European tint of two of these three (Nos. 3 and 4, C Generation); their eye-colour was very dark brown, and possibly it may have been the Indian tint. The remaining member of this generation had Indian brown eyes of a very dark shade.
It may be desirable to state that Families 4 and 5 come from different parts of Canada.
The chief feature of interest in this family is the segregation of the grey eye-colour of the Irishman among his offspring. It appears in two daughters. From what we know of analogous cases, there is little doubt that the gametes of his half-breed Indian wife carried the blue or grey factors derived from her French father. The appearance of an European brown eye-colour in Generation C, No. 6, suggests that the French grandfather had brown eyes, and that, therefore, this colour has segregated out among the gametes of the half-breed Indian mother.