Curiosities of Animal Life [pp. 232-239]

Curiosities of Animal Life.
have an anemone with two mouths,
each surrounded by its own set of tentacles. Then the processes of constriction and separation continue all
down the body of the animal from
summit to base, and the result is two
perfect anemones, each complete in
its organization. It is well that the
lower orders of creatures have none
of the laws of inheritance and primogeniture that bother mankind, or such
irregular methods of coming into the
world might breed a great deal of
trouble among them. Here, for instance, you have two anemones, which
we will call A and B, formed by the
splitting asunder of a single individual; what relation are they to each
other? Are they brother and sister
or parent and child?.And if the latter,
how is any one to decide which is the
parent? Then suppose A raises offspring in the usual way from eggs,
ihat relation are these young to B?
Are they sisters, or nieces, or grandchildrei?
Let us now look at another animal,
the stentor, or trumpet-animalcule.
This is a minute infusorian, very common in ponds and ditches, where it
forms colonies on the stems of waterweeds or submerged sticks and stones.
Some of the varieties have a deep
blue color, and a settlement of them
looks very much like a patch of blue
mould. The stentor is shaped like a
little tube, about one-sixteenth of an
inch in length, spread out at the upper
end like a trumpet, and tapering at
the lower almost to a point. When
it has fixed upon a place of abode, it
constructs a domicile, consisting of a
gelatinous sheath, perhaps half as high
as itself. zIt lives inside this sheath,
with its smaller extremity attached to
the bottom of it, and its wide, funnelshaped end projecting above the top.
When disturbed it retreats into the
house and shrinks into a globular
mass. The disc of the trumpet end
is not perfectly regular; on one side
the edge turns inward so as to form a
notch, and curls upon itself in a spiral
form. Within this spiral is the mouth,
and a long funnel-shaped throat reaches from it to the digestive cavity. Opposite the mouth there is a globular
cavity, from which a tube extends to
the lower extremity of the body. The
cavity seems to perform the functions
of a heart, and the tube takes the place
of veins and arteries. Once in threequarters of a minute this.heart-like
organ contracts and forces the fluid
which it contains into the tube; the
latter in its turn, after expanding very
sensibly to receive the flow, contracts
and returns it to the heart.
The stentor propagates by budding,
like the anemone. The first change
that takes place is a division of this
contractile vesicle into two distinct
organs at about mid-height of the body,
the lower portion developing a globular cavity like the upper one. Soon
after this a shallow pit opens in the
side of the stentor, in a line with the
new vesicle. This pit is the future
mouth. A throat or aesophagus is
next fashioned; and all being ready
for the accommodation of the new
animal the process of division begins,
and goes on so rapidly that it is all
done in about two hours.
A still more curious animal, in some
respects, than either of those we have
just mentioned is the hydra, one of
the simplest of the zoophytes. To
all intents and purposes it is nothing
but a narrow sack, about half anl inch
in length, open at one end, where the
mouth is situated, and attaching itself
by the other to pond-lilies, duck-weeds,
or stones on the margins of lakes.
Around' the mouth it has from five to
eight slender tentacles, which are used
as feelers and for the purpose of seizing
the food. What it does with its food
after it has swallowed it is, strange as
the statement may sound, a question
to which naturalists have not yet
found a satisfactory answer; for the
hydra has no digestive organs, and its
stomach is merely a pouch formed by
the folding in of the outer skin. It
has no glands, no mucous membrane,
no appliances of any sort for the performance of the chemical process
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