Audubon County journal. (Exira, Iowa) 1884-1993, 1898-09-01
ANTS AND FLlEs.
A Naturalist Proves How They Distribute
Yeasts and Molds.

A Naturalist Proves How They Distribute
Yeasts and Molds.
The part played by insects in the
distribution of minute vegetable or
ganisms has been made the subject
of an interesting investigation by
DR.. Amedeo Berlese at the Portici
Laboratory for Agricultural Chem
istry. That they do perform this
task, often very mischievous one,
has long been known, but the pro-
fessor, as is shown in the current
number of Nature, has proved that,
for good or evil, they are more ac-
tive than had been hitherto ascer-
tanned. Ants were the subjects Of
his first experiments. He had fire.
quently detected the cells Of two all
coholic yeasts hidden in assures of
the bark on the trunks of both fruit
and forest trees. These he suspected
to have been transported by the
ants, which were constantly travel
ing up and down the trunks, and it
seemed likely that flies might COOP
crate in the work. First, he "put
the question" to the ants. He col
lected a large number of species
which is very common in vineyards.
They were allowed access to punches
Of grapes which had been carefully
sterilized and afterward placed I'M
der conditions that prevented the
possibility of any introduction of
molds or yeasts from the outer air.
The result, in less than fortnight,
was that all the punches which the
ants could visit were abundantly in
tested with yeasts and molds, while
several others which had been pre-
served even for much longer time
in sterilized vessels from which the
ants were excluded, had neither
molds nor yeasts or bacteria on
their surfaces.
DR.. Berlese then turned his atten-
ton to the flies. His methods of in
QUESTION, we fear, would not be ap-
proved by those who share Corporal
Toby's view and are merciful even
to the house fly and the bluebottle.
In fact, these torments of the hui
man race must have had decided
ly bad time in the laboratory. The
first experiment, however, was sim
pie and humane A number of bits
of sterilized meat were set out on
terrace, some of them covered by
wire gauze, others accessible to the
flies. After two hours exposure to
them and 10 to the air, yeasts were
found to be much more abundant
in the fOrmer-indeed DR.. Berlese
estimates that the quantity of yeasts
conveyed by flies is about 26 times
as great as is brought by the air.
Similar experiments were made
with grapes, and with similar re-
suits. The next point to settle was
the precise way in which the trans
port was effected. Itwas first ascer-
tanned that ferments were often
more frequent in the bodies of flies
than on their legs and feet; next,
cells simila-' to those of yeast were
detected in their excreta. Itremain-
ed, then, to study the passage of
these cells through the digestive APP
paratus of ssheinsect. Common blue
bottles, or meat flies, were selected
for this purpose, and a large num-
Der of experiments were made on
them, but some other flies and Gel
lar midges were also tested. 1t was
proved in all cases that when
the flies were fed with sterilized
material. the excreta contained no
yeasts, but when they had diet of
pure cultures of sundry yeast the
exoreta soon contained in great
quantities the yeasts that were in
the food. These cells also were
not dead, but living. If collected,
they duly terminated and devel-
oped, though the rate of the
process and the abundance of the
result were found to depend to a
considerable extent on the tempera-
ture maintained. Further expert
ments indicated that the cells in
creased in number in passing
through tho body of the fly, and the
general result of the whole series
was to demonstrate that ants and
certain flies play an important part
not only in the distribution Gas was
already known), but also in the
preservation and multiplication of
alcoholic ferments. Insects, in fact,
contribute far more than atmos-
pheric air to the dissemination of
yeasts, which are conveyed internal
ly rather than externally. In some
cases this distributing agency may
be exercise, for good, but we sus-
pect it is fa, more often potent for
evil. Standard.
One of Perry's Lake Erie Fleet.
Buried deep in the sands at the