After much consideration and many inquiries, I determined, in 1885, on experimenting with sweet peas, which were suggested to me both by Sir Joseph Hooker and by Mr. Darwin.... The result clearly proved Regression; the mean Filial deviation was only one-third that of the parental one, and the experiments all concurred. The formula that expresses the descent from one generation of a people to the next, showed that the generations would be identical if this kind of Regression was allowed for.
Ch. XX Heredity (1909 ed.) - Memories of My Life (1908)