these surprising performances of animals as manifestations of what we
call instinct, and the mysticism of natural philosophy has ever shown
a predilection for this theme; but if we regard instinct as the
outcome of the memory or reproductive power of organised substance,
and if we ascribe a memory to the race as we already ascribe it to
the individual, then instinct becomes at once intelligible, and the
physiologist at the same time finds a point of contact which will
bring it into connection with the great series of facts indicated
above as phenomena of the reproductive faculty. Here, then, we have
a physical explanation which has not, indeed, been given yet, but the
time for which appears to be rapidly approaching.

When, in accordance with its instinct, the caterpillar becomes a
chrysalis, or the bird builds its nest, or the bee its cell, these
creatures act consciously and not as blind machines. They know how
to vary their proceedings within certain limits in conformity with
altered circumstances, and they are thus liable to make mistakes.
They feel pleasure when their work advances and pain if it is
hindered; they learn by the experience thus acquired, and build on a
second occasion better than on the first; but that even in the outset
they hit so readily upon the most judicious way of achieving their
purpose, and that their movements adapt themselves so admirably and
automatically to the end they have in view--surely this is owing to
the inherited acquisitions of the memory of their nerve substance,
which requires but a touch and it will fall at once to the most
appropriate kind of activity, thinking always, and directly, of
whatever it is that may be wanted.

Man can readily acquire surprising kinds of dexterity if he confines
his attention to their acquisition. Specialisation is the mother of