of particular families to grave constitutional disease. Indeed, the secret history of a family is quite as important in its eugenic aspect as its public history ; but one cannot expect persons to freely unlock their dark closets and drag forth family skeletons into the light of day. It was necessary in such a work as this to submit to considerable limitations, while turning to the fullest account whatever could be stated openly without giving the smallest offence to any of the persons concerned.
One limitation against which I still chafe in vain is the impracticability of ascertaining so apparently simple a matter as the number of kinsfolk of each person in each specific degree of near kinship, without troublesome solicitations. It was specially asked for in the circular, but by no means generally answered, even by those who replied freely to other questions. The reason must in some cases have been mere oversight or pure inertia, but to a large extent it was due to ignorance, for I was astonished to find many to whom the number of even their near kinsfolk was avowedly unknown. Emigration, foreign service, feuds between near connections, differences of social position, faintness of family interest, each produced their several effects, with the result, as I have reason to believe, that hardly one-half of the persons addressed were able, without first making inquiry of others, to reckon the number of their uncles, adult nephews, and first cousins. The isolation of some few from even their nearest relatives was occasionally so complete that the