eful examinations of the subject invalidate the views heretofore
held, and it must be acknowledged that when both parties are healthy
there is no more liability of mental incompetency in the children of
cousins, than in the offspring of persons more remotely related. It
must be added, however, that there are other reasons why the marriage
of cousins is not to be generally recommended. Besides the fact that
the feeling existing between cousins is often only that which is felt
by brothers and sisters for each other, there is the still more
important fact that on account of the blood relation, unions of this
kind are more apt than others to bring together persons having similar
morbid tendencies.

_4. Persons having serious congenital deformities should not marry._

The reason for this rule is obvious. Persons suffering with serious
congenital defects, as natural blindness, deafness, deformity of the
limbs, or defective development of any part, will be more or less likely
to transmit the same deformities or deficiencies to their children.
There are, of course, cases of natural blindness, as well as of
disability in other respects, to which this rule does not apply, the
natural process of development not being seriously defective. It has
even been observed that there is a slight tendency to the reproduction
in the offspring, of deformity which has been artificially produced
in the parents, and has existed for a long time.

Many ancient nations observed this rule. Infants born cripples were
strangled at birth or left to die. A Spartan king was once required
by his people to pay a heavy fine for taking a wife who was inferior
in size.

_5. Criminals should not marry._

It has been satisfactorily shown by thorough and scientific
investigation that criminals often receive their evil proclivities
from their parents. What are known as the criminal classes, which are
responsible for the greater part of the crime committed, are constantly
and greatly on the increase. There is no doubt but that inheritance
is largely responsible for the continued increase of crime and
criminals. A drunkard begets in his child a thirst for liquor, which
is augmented by the mother's use of ale or lager during gestation and
nursing, and the child enters the world with a natural taste for
intoxicants. A thief transmits to his offspring a secretive, dishonest,
sneaking disposition; and the child comes into the world ticketed for
the State prison by