in marriage has also
been frequent in the middle western counterpart of the Jukes, the
"Tribe of Ishmael."[57]

[Footnote 56: Dugdale, op. cit., p. 16.]

[Footnote 57: McCulloch, _Tribe of Ishmael_.]

A more recent study of hereditary degeneracy is that of the "Zero
Family" in Switzerland.[58] Here the first degenerate was the product
of two successive consanguineous marriages, both with a branch tainted
_with insanity_. In spite of his bad ancestry he lived to the age of
106 years. He married an Italian woman of questionable antecedents,
and was the father of a large family. Three hundred and ten of his
descendants are mentioned, of whom many are still young. Of these 310,
74 died in early childhood, 55 are or were vagabonds, 58 were
weak-minded or idiotic and 23 were criminals. Fifty-two were of
illegitimate birth. Although some are counted in more than one
category, the record is appalling. In this family however, the
marriages were nearly all with foreign women, and the effect of
consanguinity was only the intensification of the neurosis in the
first two generations.

[Footnote 58: Joerger, "Die Familie Zero." Reviewed by Gertrude C.
Davenport, in the _American Journal of Sociology_, Nov., 1907.]

Dr. Bemiss found that 300 or 7.7 per cent of the offspring of
consanguineous marriages were subject to scrofula.[59] This is a
disease which is almost universally recognized as hereditary, and
which we should therefore expect to find intensified by double
heredity. But 7.7 per cent is obviously too high; otherwise most of
the scrofulous must be the offspring of marriages of kindred. About
one per cent of the children of my own correspondence cases were
reported as scrofulous. And while the United States Census reports but
3.9 per cent of the blind as the offspring of consanguineous
marriages, the percentage of the blind from scrofula is 6.1.[60] The
blind from scrofula of consanguineous parentage were 2.8 per cent of
all the blind of consanguineous parentage, while all the blind from
scrofula were 1.8 per cent of all the blind. Consanguinity, then,
seems appreciably to intensify scrofula, but there is no indication
that scrofula is ever caused by parental consanguinity.

[Footnote 59: Bemiss, see _Trans. of Am. Med. Asso._, vol. xi, 1858,
p. 420.]

[Footnote 60: _The Blind and the Deaf._ Special Report of 12th Census,
1906.]

CHAPTER V

CONSANGUINITY AND MENTAL DEFECT

Idiocy, perhaps more than any o