act. In the absence, however, of a corresponding table concerning
fertile women, nothing is hereby absolutely proved, and, at most,
only a probability established.

Kisch, more recently (in his _Sexual Life of Woman_), has dealt
fully with this question, and reaches the conclusion that it is
"extremely probable" that the active erotic participation of the
woman in coitus is an important link in the chain of conditions
producing conception. It acts, he remarks, in either or both of
two ways, by causing reflex changes in the cervical secretions,
and so facilitating the passage of the spermatozoa, and by
causing reflex erectile changes in the cervix itself, with slight
descent of the uterus, so rendering the entrance of the semen
easier. Kisch refers to the analogous fact that the first
occurrence of menstruation is favored by sexual excitement.

Some authorities go so far as to assert that, until voluptuous
excitement occurs in women, no impregnation is possible. This
statement seems too extreme. It is true that the occurrence of
impregnation during sleep, or in anaesthesia, cannot be opposed to
it, for we know that the unconsciousness of these states by no
means prevents the occurrence of complete sexual excitement. We
cannot fail, however, to connect the fact that impregnation
frequently fails to occur for months and even years after
marriage, with the fact that sexual pleasure in coitus on the
wife's part also frequently fails to occur for a similar period.

"Of all human instincts," Pinard has said,[422] "that of reproduction is
the only one which remains in the primitive condition and has received no
education. We procreate to-day as they procreated in the Stone Age. The
most important act in the life of man, the sublimest of all acts since it
is that of his reproduction, man accomplishes to-day with as much
carelessness as in the age of the cave-man." And though Pinard himself, as
the founder of puericulture, has greatly contributed to call attention to
the vast destinies that hang on the act of procreation, there still
remains a lamentable amount of truth in this statement. "Future
generations," writes Westermarck in his great history of moral ideas,[423]
"will probably with a kind of horror look back at a period when the most
important, and in its consequences the most far-reaching, function which
has fallen to the lot of