even a sufficient account, of the progress of fermentative action, by
means of saprophytic organisms, on great masses of tissue; my
observations have been incidental, but they lead me to the conclusion
that the fermentative process is not only not carried through by what
are called saprophytic bacteria, but that a _series_ of fermentative
organisms arise, which succeed each other, the earlier ones preparing
the pabulum or altering the surrounding medium, so as to render it
highly favorable to a succeeding form. On the other hand, the
succeeding form has a special adaptation for carrying on the
fermentative destruction more efficiently from the period at which it
arises, and thus ultimately of setting free the chemical elements
locked up in dead organic compounds.

That these later organisms are saprophytic, although not bacterial,
there can be no doubt. A set of experiments, recorded by me in the
proceedings of this society some years since, would go far to
establish this (_Monthly Microscopical Journal_, 1876, p. 288). But it
may be readily shown, by extremely simple experiments, that these
forms will set up fermentative decomposition rapidly if introduced in
either a desiccated or living condition, or in the spore state, into
suitable but sterilized pabulum.

Thus while we have specific ferments which bring about definite and
specific results, and while even infusions of proteid substances may
be exhaustively fermented by saprophytic bacteria, the most important
of all ferments, that by which nature's dead organic masses are
removed, is one which there is evidence to show is brought about by
the successive vital activities of a series of adapted organisms,
which are forever at work in every region of the earth.