great
degree my
theory;
but none
of the
cases of
difficulty,
to the
best of my
judgment,
annihilate
it. On the
other
hand, the
fact that
instincts
are not
always
absolutely
perfect
and are
liable to
mistakes;—that
no
instinct
has been
produced
for the
exclusive
good of
other
animals,
but that
each
animal
takes
advantage
of the
instincts
of
others;—that
the canon
in natural
history,
of “natura
non facit
saltum” is
applicable
to
instincts
