The Dawn of Reason; or, Mental Traits in the Lower AnimalsWeir, James, Jr.
Science
The Dawn of Reason; or, Mental Traits in the Lower Animals
Weir, James, Jr.
Psychology, Comparative; Reason
Here was an act which required, so it seemed to me, correlative
ideation, and which was doubly surprising, because occurring in an
animal of such extremely simple organization. This observation was
substantiated, however, by the testimony of Professor Carter, an English
biologist, which came to my notice a week or so thereafter. This
investigator witnessed a similar act in an animalcule belonging, it is
true, to another family, but which is almost, if not quite, as simple in
its organization as Stentor. He does not designate the particular
rhizopods that he had under observation, yet from his language, we are
able to classify them approximately. His account is so very interesting
that I take the liberty of quoting him in full.
"On one occasion, while investigating the nature of some large,
transparent, spore-like elliptical cells (fungal?) whose protoplasm was
rotating, while it was at the same time charged with triangular grains
of starch, I observed some actinophorous rhizopods creeping about them,
which had similar shaped grains of starch in their interior; and having
determined the nature of these grains by the addition of iodine, I
cleansed the glasses, and placed under the microscope a new portion of
the sediment from the basin containing these cells and actinophryans for
further examination, when I observed one of the spore-like cells had
become ruptured, and that a portion of its protoplasm, charged with the
triangular starch grains, was slightly protruding through the crevice.
It then struck me that the actinophryans had obtained their starch
grains from this source; and while looking at the ruptured cell, an
_actinophrys_ made its appearance, and creeping round the cell, at last
arrived at the crevice, from which it extricated one of the grains of
starch mentioned, and then crept off to a good distance. Presently,
however, it returned to the same cell; and although there were now no
more starch grains protruding, the _actinophrys_ managed again to
extract one from the interior through the crevice. All this was repeated
several times, showing that the _actinophrys_ instinctively knew that
those were nutritious grains, that they were contained in this cell, and
that, although each time after incepting a grain it went away to some
distance, it knew how to find its way back to the cell again which
furnished this nutriment.
"On another occasion I saw an _actinophrys_ station itself close to a
ripe spore-cell of _pythium_, which was situated on a filament of
_Spirogyra crassa_; and as the young ciliated monadic germs issued forth
one after another from the dehiscent spore-cell, the _actinophrys_
remained by it and caught every one of them, even to the last, when it
retired to another part of the field, as if instinctively conscious that
there was nothing more to be got at the old place.
Public-domain text, read in full here on John Shaqi.
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