nine-tenths related to men; but it is eminently liable to be transmitted
through women. In the case given by Dr. Earle, members of eight related
families were affected during five generations: these families consisted of
sixty-one individuals, namely, of thirty-two males, of whom nine-sixteenths
were incapable of distinguishing colour, and of twenty-nine females, of whom
only one-fifteenth were thus affected. Although colour-blindness thus
generally clings to the male sex, nevertheless, in one instance in which it
first appeared in a female, it was transmitted during five generations to
thirteen individuals, all of whom were females. The haemorrhagic diathesis,
often accompanied by rheumatism, has been known to affect the males alone
during five generations, being transmitted, however, through the females. It
is said that deficient phalanges in the fingers have been inherited by the
females alone during ten generations. In another case, a man thus deficient in
both hands and feet, transmitted the peculiarity to his two sons and one
daughter; but in the third generation,--out of nineteen grandchildren, twelve
sons had the family defect, whilst the seven daughters were free. In ordinary
cases of sexual limitation, the sons or daughters inherit the peculiarity,
whatever it may be, from their father or mother, and transmit it to their
children of the same sex; but generally with the haemorrhagic diathesis, and
often with colour-blindness, and in some other cases, the sons never inherit
the peculiarity directly from their fathers, but the daughters alone transmit
the latent tendency, so that the sons of the daughters alone exhibit it. Thus
the father, grandson, and great-great-grandson will exhibit a peculiarity,--
the grandmother, daughter, and great-grand-daughter having transmitted it in a
latent state. Hence we have, as Mr. Sedgwick remarks, a double kind of atavism
or reversion; each grandson apparently receiving and developing the
peculiarity from his grandfather, and each daughter apparently receiving the
latent tendency from her grandmother.

From the various facts recorded by Dr. Prosper Lucas, Mr. Sedgwick, and