DISCUSSION OF. THE DATA OF EYE COLOUR.
Preliminary Remarks.-Data.-Persistence of Eye-Colour in the Popula
tion.-Fundamental Eye-Colours.-Principles of Calculation.-Results.
Preliminary Remarks.-In this chapter I will test the conclusions respecting stature by an examination into hereditary Eye-colour. Supposing all female measures to have been transmuted to their male equivalents, it has been shown (1) that the possession of each unit of peculiarity of stature in a man [that is of each unit of difference from the average of his race] when the man's ancestry is unknown, implies the existence on an average of just one-third. of a unit of that peculiarity in his "Mid-Parent," and consequently of the same amount in each of his parents ; also just onethird of a unit in his Son ; (2) that each unit of peculiarity in each ancestor taken singly, is reduced in transmission according to the following average scale ;a Parent transmits only 4, and a Grand-Parent only T-9.
Stature and Eye-colour .are not only different as qualities, but they are more contrasted in hereditary