Scientific American Supplement, No. 643 | Page 4

former has reference to the
group of organisms to which I have for so many years directed your
attention, viz., the "monads," which throughout I have called
"putrefactive organisms."
There can be no longer any doubt that the destructive process of
putrefaction is essentially a process of fermentation.
The fermentative saprophyte is as absolutely essential to the setting up
of destructive rotting or putrescence in a putrescible fluid as the torula
is to the setting up of alcoholic fermentation in a saccharine fluid.
Make the presence of torulæ impossible, and you exclude with
certainty fermentative action.
In precisely the same way, provide a proteinaceous solution, capable of
the highest putrescence, but absolutely sterilized, and placed in an
optically pure or absolutely calcined air; and while these conditions are
maintained, no matter what length of time may be suffered to elapse,
the putrescible fluid will remain absolutely without trace of decay.
But suffer the slightest infection of the protected and pure air to take
place, or, from some putrescent source, inoculate your sterilized fluid
with the minutest atom, and shortly turbidity, offensive scent, and
destructive putrescence ensue.
As in the alcoholic, lactic, or butyric ferments, the process set up is
shown to be dependent upon and concurrent with the vegetative
processes of the demonstrated organisms characterizing these ferments;
so it can be shown with equal clearness and certainty that the entire
process of what is known as putrescence is equally and as absolutely
dependent on the vital processes of a given and discoverable series of
organisms.
Now it is quite customary to treat the fermentative agency in
putrefaction as if it were wholly bacterial, and, indeed, the putrefactive

group of bacteria are now known as saprophytes, or saprophytic
bacteria, as distinct from morphologically similar, but physiologically
dissimilar, forms known as parasitic or pathogenic bacteria.
It is indeed usually and justly admitted that _B. termo_ is the exciting
cause of fermentative putrefaction. Cohn has in fact contended that it is
the distinctive ferment of all putrefactions, and that it is to
decomposing proteinaceous solutions what _Torula cerevisiæ_ is to the
fermenting fluids containing sugar.
In a sense, this is no doubt strictly true: it is impossible to find a
decomposing proteinaceous solution, at any stage, without finding this
form in vast abundance.
But it is well to remember that in nature putrefactive ferments must go
on to an extent rarely imitated or followed in the laboratory. As a rule,
the pabulum in which the saprophytic organisms are provided and
"cultured" is infusions, or extracts of meat carefully filtered, and, if
vegetable matter is used, extracts of fruit, treated with equal care, and if
needful neutralized, are used in a similar way. To these may be added
all the forms of gelatine, employed in films, masses and so forth.
But in following the process of destructive fermentation as it takes
place in large masses of tissue, animal or vegetable, but far preferably
the former, as they lie in water at a constant temperature of from 60° to
65° F., it will be seen that the fermentative process is the work, not of
one organism, nor, judging by the standard of our present knowledge,
of one specified class of vegetative forms, but by organisms which,
though related to each other, are in many respects greatly dissimilar,
not only morphologically, but also embryologically, and even
physiologically.
Moreover, although this is a matter that will want most thorough and
efficient inquiry and research to understand properly its conditions, yet
it is sufficiently manifest that these organisms succeed each other in a
curious and even remarkable manner. Each does a part in the work of
fermentative destruction; each aids in splitting up into lower and lower
compounds the elements of which the masses of degrading tissue are

composed; while, apparently, each set in turn does by vital action,
coupled with excretion, (1) take up the substances necessary for its own
growth and multiplication; (2) carry on the fermentative process; and (3)
so change the immediate pabulum as to give rise to conditions suitable
for its immediate successor. Now the point of special interest is that
there is an apparent adaptation in the form, functions, mode of
multiplication, and order of succession in these fermentative organisms,
deserving study and fraught with instruction.
Let it be remembered that the aim of nature in this fermentative action
is not the partial splitting of certain organic compounds, and their
reconstruction in simpler conditions, but the ultimate setting free, by
saprophytic action, of the elements locked up in great masses of
organic tissue--the sending back into nature of the only material of
which future organic structures are to be composed.
I have said that there can be no question whatever that Bacterium termo
is the pioneer of saprophytes. Exclude _B. termo_ (and therefore with