culiarities and organization of the female.

MODES OF DIOECIOUS REPRODUCTION.--A very familiar illustration of one
mode is found in the common domestic fowl, the egg of which vivified
within the ovarium, is afterward expelled and hatched by the simple
agency of warmth. This mode of reproduction is called _oviparous
generation_.

The ovaries, as well as all their latent germs, are _remarkably_
influenced by the first fecundation. It seems to indicate monogamy as
the rule of higher sexual reproduction. The farmer understands that if
he wishes to materially improve his cows, the first offspring must be
begotten by a better, purer breed, and all that follow will be
essentially benefited, even if not so well sired. Neither will the best
blood exhibit its most desirable qualities in the calves whose mothers
have previously carried inferior stock. So that there are sexual
ante-natal influences which may deteriorate the quality of the progeny.
The Jews understood this principle, in the raising up of sons and
daughters unto a deceased brother. The fact that the sexual influence of
a previous conception is not lost, is illustrated when, in a second
marriage, the wife bears a son or daughter resembling bodily or
mentally, or in both of these respects the former husband. This
indicates a union for life by natural influences which never die out.

With some species of fish and reptiles, the egg is impregnated
internally, and the process of _laying_ commences immediately, but it
proceeds so slowly through the excretory passages, that it is hatched
and born alive. This is called _ovo-viviparous generation_.

As we rise in the scale of organization, animals are more completely
developed, and greater economy is displayed in their preservation. The
germ passes from the ovary into an organ prepared for its reception and
growth, to which, after fecundation, it becomes attached, and where it
remains until sufficiently developed to maintain respiratory life. This
organ is called the _womb_, or _uterus_, and is peculiar to most
mammalia. This mode of reproduction is termed _viviparous generation_.

The kangaroo and oppossum are provided with a pouch attached to the
abdomen, which receives the young born at an early stage of development.
They remain in contact with the mammae, from which they obtain their
nourishment, until their growth is sufficiently completed to maintain an
independent existence. This is called _marsupial generation_. Th