ally apt to be
found in families in which consanguineous marriages occur and this fact,
together with the pedigrees [which he studied], suggests that it is due
to the absence of some factor that controls the process of cornification
of the skin. On this hypothesis a normal person who belongs to an
affected family may marry into a normal family with impunity, but cousin
marriages are to be avoided." See Davenport, C. B., _Heredity in
Relation to Eugenics_, p. 134. New York, 1911.

[26] Its eugenics is to be effected through the mental exertion of
mothers. And we have lately been in correspondence with a western
attorney who is endeavoring to form an association of persons who will
agree to be the parents of "willed" children. By this means, he has
calculated (and sends a chart to prove it) that it will require only
four generations to produce the Superman.

[27] _Life and Letters of Charles Darwin_, Vol. I, p. 302, New York,
1897. The letter is dated 1844.

[28] Goddard, H. H., _Feeble-mindedness_, p. 359. New York, the
Macmillan Company, 1914.

[29] For a review of the evidence consult an article on "Telegony" by
Dr. Etienne Rabaud in the _Journal of Heredity_, Vol. V, No. 9, pp.
389-400; September, 1914.

[30] It will be recalled that the coefficient of correlation measures
the resemblance between two variables on a scale between 0 and-1 or +1.
If the correlation is zero, there is no constant relation; if it is
unity, any change in one must result in a determinate change in the
other; if it is 0.5, it means that when one of the variables deviates
from the mean of its class by a given amount, the other variable will
deviate from the mean of its class by 50% of that amount (each deviation
being measured in terms of the variability of its own class, in order
that they may be properly comparable.)

[31] Sidis, Boris, M.A., Ph.D., M.D., "Neurosis and Eugenics," _Medical
Review of_ _Reviews_, Vol. XXI, No. 10, pp. 587-594, New York, October,
1915. A psychologist who writes of "some miraculous germ-plasm
(chromatin) with wonderful dominant 'units' (Chromosomes)" is hardly a
competent critic of the facts of heredity.

[32] In a letter to the _Journal of Heredity_, under date of August 4,
1916.

[33] Galton, Francis, _Inquiries into Human Faculty_, p. 167, London,
1907.

[34] Woods, Frederick Adams, _Heredity in Royalty_, New York, 1906.

[35] _Op. cit._, pp. 170-171.

[36] Thorndike, E. L., "Measurements of Twin