t for it and for the father
as the giver of life, were bred into the boy at an early age. Moreover a
certain shyness, which often makes it more difficult for fathers to talk
to their sons on these matters than for the mothers to do so, would not
have existed if they themselves as children and youth had been educated
to a complete knowledge of the sex-life by one or both parents. The
cause of this shyness is in many cases ignorance of how to present the
facts, and a misconception of the difficulties of speaking to a
pure-minded child about them. Nothing surprises the parent more than the
way difficulties vanish when once the course of instruction to the youth
has been entered upon.

In the lower life the father seldom cares for his offspring; and this is
true among the fishes, where neither parent as a rule assumes any other
responsibility than properly disposing of and fertilizing the eggs.
Where, however, any care is taken, it not infrequently devolves upon the
father instead of the mother. This is true of the fresh-water black
bass and of the stickleback, where the father protects the eggs until
they are hatched, and protects and cares for the young fish. In the case
of the stickleback, the father even makes a nest to contain the eggs.

Thus far, the process of the renewal of life is, so to speak,
impersonal. The eggs are laid by one fish and fertilized by the other,
this being necessary to the development of the young. The parents are
endowed with an instinct which informs them when the time is at hand;
and the male fish guided by this instinct applies the fertilizing
material where it is needed,--that is, over the surface of the
fresh-laid eggs. The number of eggs laid by fishes should be noticed, as
it is a fact which will be useful later. Several millions of eggs have
been counted in the ovaries of one fish. The number of fertilizing cells
in one testicle would be incalculable. Fish eggs and young fishes are
liable to many fatalities; they are destroyed in immense numbers.
Consequently, if the race is to survive, there must be an almost
inexhaustible supply.

Fishes kept in confinement will not as a rule multiply. Nothing is so
sensitive as the reproductive system. Lacking certain stimuli which it
finds in its natural surroundings, it will not become active. The
goldfish in the globe will, if a female, have the ovary containing
undeveloped ova, the male will have the testicles containing the
fertilizing cells,