Difference between the best specimens of a poor race and the mediocre ones of a high race; typical centres to which races tend to revert; delicacy of highly-bred animals; their diminished fertility; the misery of rigorous selection; it is preferable to replace poor races by better ones; strains of emigrant blood; of exiles.
SELECTION AND RACE
From Inquiries into Human Faculty and Its Development by Francis Galton.
