egg produced by the female, and thus to start a new and independent
life-form. This life-form, thus started, grows according to the laws
of its becoming more and more, until, at the expiration of a fixed
period, which varies greatly in different animals, it becomes a
complete young individual, of the nature and kind of its parents.
The fertilization of the ovum in the female is called conception;
its growing state is called gestation, and its birth, on becoming a
separate being, is called parturition. In its growing condition, and
before its birth, the new young life form is known as the foetus.

Now it is the fertilization of the ovum in the female (and from now
on, it is only of the male and female in the human family that mention
will be made) by the male, in the woman, by the man, that is of
supreme interest and importance to both the parties concerned in
producing this result. How this is brought about is substantially as
follows:

As already stated, the infertile ovum, or egg, is produced by the
woman. Such production begins at what is known as the age of puberty,
or when the hair begins to grow upon the pubic parts of the female
body. The time of the appearance of this phenomenon in feminine life
varies from the age of nine or ten years to fifteen or sixteen. The
average, for most girls, is fourteen years of age. At this time
the formation of ova, or eggs, in the female body begins, and it
continues, in most women, at regular intervals of once in twenty-eight
days, except during pregnancy and lactation, for a period of about
thirty years. During all this time, under favorable conditions, it is
possible for the ovum produced by the woman to become fertilized, if
it can meet the sperm of the male.