part of a point, or in the relations of the parts of a segment of a
curve to one another, suffices to alter the law of its whole path,
and so in like manner an infinitely small influence exercised by the
parent organism on the molecular disposition of the germ {78} may
suffice to produce a determining effect upon its whole farther
development.

What is the descent of special peculiarities but a reproduction on
the part of organised matter of processes in which it once took part
as a germ in the germ-containing organs of its parent, and of which
it seems still to retain a recollection that reappears when time and
the occasion serve, inasmuch as it responds to the same or like
stimuli in a like way to that in which the parent organism responded,
of which it was once part, and in the events of whose history it was
itself also an accomplice? {79} When an action through long habit or
continual practice has become so much a second nature to any
organisation that its effects will penetrate, though ever so faintly,
into the germ that lies within it, and when this last comes to find
itself in a new sphere, to extend itself, and develop into a new
creature--(the individual parts of which are still always the
creature itself and flesh of its flesh, so that what is reproduced is
the same being as that in company with which the germ once lived, and
of which it was once actually a part)--all this is as wonderful as
when a grey-haired man remembers the events of his own childhood; but
it is not more so. Whether we say that the same organised substance
is again reproducing its past experience, or whether we prefer to
hold that an offshoot or part of the original substance has waxed and
developed itself since separation from the parent stock, it is plain
that this will constitute a difference of degree, not kind.