mal developments. From age to
age, the type is _constant_, and preserves a race-unity. The crossings
of the races are only transient deviations, not capable of perpetuation,
and quickly return again to the original stock. This force is
persistent, for inasmuch as the individual represents the race, so does
his offspring represent the parental characteristics, in tastes,
proclivities, and morals, as well as in organic resemblances. This
constancy is unaccountable, and more mysterious than the occasional
malformation of germs in the early period of foetal life. If to every
deviation from that original form and structure, which gives character
to the productions of nature, we apply the term _monster_, we shall find
but very few, and from this whole class there will be a very small
number indeed of _sexual_ malformations. If the sexes be deprived of the
generative organs, they approach each other in disposition and
appearance. All those who are partly male and partly female in their
organization, unite, to a certain extent, the characteristics of both
sexes. When the female loses her prolific powers, many of her sexual
peculiarities and attractions wane.

DIOECIOUS REPRODUCTION.

_Dioecious_ is a word derived from the Greek, and signifies _two
households;_ hence, _dioecious reproduction_ is sexual generation by
male and female individuals. Each is distinguished by sexual
characteristics. The male sexual organs are complete in one individual,
and all the female organs belong to a separate feminine organization. In
some of the vertebrates, impregnation does not require sexual congress;
in other words, fecundation may take place _externally_. The female fish
of some species first deposits her ova, and afterwards the male swims to
that locality and fertilizes them with sperm.

In higher orders of animals, fecundation occurs _internally_, the
conjunction of the sperm and germ cells requiring the conjugation of the
male and female sexual organs. The sperm-cells of the male furnish the
quickening principle, which sets in play all the generative energies,
while the germ-cell, susceptible to its vivifying presence, responds
with all the conditions necessary to evolution. The special laboratory
which furnishes spermatic material is the _testes_, while the stroma of
the _ovaries_ contributes the germ-cell. Several different modes of
reproducing are observed when fecundation occurs within the body, which
vary according to the pe