<h2><SPAN name="THE_HIBERNATION_OF_ANIMALS" id="THE_HIBERNATION_OF_ANIMALS"></SPAN> THE HIBERNATION OF ANIMALS.</h2>
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<p class="drop-cap">NATURE presents no greater or
more curious phenomenon than
the habit of certain animals to
conceal themselves and lie dormant,
in a lethargic sleep, for weeks
and months. It is known that in perfect
hibernators the processes of nature
are interrupted during the period of
this long insensibility. Breathing is
nearly, and in some animals, entirely
suspended, and the temperature of the
blood even in the warmer blooded animals,
falls so low that how life can be
maintained in them is a great mystery.</p>
<p>A variety of Rocky Mountain ground
squirrels, when in perfect hibernation,
says an observer, has a temperature
only three degrees above freezing point
of water, and when taken from their
burrows are as rigid as if they were not
only dead, but frozen. But a few minutes
in a warm room will show that
they are not only alive, but full of life.</p>
<p>As to the suspension of breathing in
hibernators, the fact is proved sufficiently
in the instances of the raccoon
and the woodchuck. When they have
laid themselves away for the winter
sleep they roll themselves up comfortably
and press their noses in such a
position against their hinder parts that
it would be an absolute impossibility
for them to draw a breath. It is generally
supposed that the bear rolls
itself up in this way and does not
breathe, but the holes melted in the
snow beneath which the animal frequently
stows itself, under a covering
of leaves, prove that it does breathe
while in its lethargy.</p>
<p>The marmot family produces the
soundest winter sleepers. When the
marmot is in its peculiar state of hibernation
the electric spark will not rouse
it. The most noxious gases do not
affect it in the slightest. If its temperature
is raised above that at which the
animal breathed in its natural state it
will die almost immediately.</p>
<p>Our own familiar wild animals, the
bear, the raccoon, and the woodchuck—the
so-called ground-hog—are classed
as perfect hibernators, because they
store no food for winter, but have
acquired or provided themselves with
a thick, fatty secretion between the
skin and flesh, which, it is supposed,
supplies them with sustenance. As a
matter of fact, although dormant animals
absorb fat, it does not enter into
their digestive organs. Food introduced
into the stomach of a hibernating
animal, or reptile, by force or
artificial means, will be found undigested
at all stages of its lethargy,
for it invariably goes into its peculiar
state on an empty stomach. That is
one of the mysteries of the phenomenon,
not so great, however, as the fact
that bears and woodchucks produce
their young during their winter sleep.
The male bear is frequently roused
from his sleep and is found by the
woodsman roaming about in mid-winter,
but they have never known, they say,
a female bear to be killed after the season
for hibernation has set in.</p>
<p>Squirrels are only partial hibernators,
from the fact that they work all
summer and fall storing great quantities
of food to supply them when hunger
wakes them up during the winter,
some of them, no doubt, spending very
little time in a lethargic sleep.</p>
<p>The common land tortoise, no matter
where it may be, and it is a voracious
feeder, goes to sleep in November
and does not wake up again till
May, and that curious animal, the
hedgehog, goes to sleep as soon as the
weather gets cold and remains in unbroken
slumber six months.</p>
<p>Bats, at the beginning of cold
weather, begin to huddle together in
bunches in hollow trees, dark corners
in deserted houses, and in caves and
crevices in the rocks. They gradually
lose all sensibility, and continue in a
comatose state until the return of genuine
warm weather. When you see the
first bat of the season fluttering at
nightfall you can be sure that warm
weather has come to stay. The little
hooks at the end of one of the joints of
each wing are what the bat hangs itself
up by when it goes to sleep, whether
for a day or for months. When the
bats are clustering for hibernation one
of the number hangs itself up by its
hooks, head downward, and the others
<span class="pagenum"><SPAN name="Page_85" id="Page_85">[Pg 85]</SPAN></span>
cling to it. It is on record that sixty
bats have been found in one cluster, the
entire weight of the lot being sustained
by the one bat clinging with its hooks
to whatever it had fastened them to at
the start—a weight of at least ten
pounds. The position of the central
bat in such a cluster would be like that
of a man hanging by his thumb-nails
and supporting the weight of fifty-nine
other men. So completely is animation
suspended in the bat during the
cold months that no test yet applied
has induced it to show the least sign of
life. Torpid bats have been inclosed
by the hour in air-tight glass jars and
not a particle of oxygen in the jars
has been exhausted when they were
taken out, showing that the bats had
not breathed.</p>
<p>As cold drives certain animals, insects,
and reptiles to a state of torpidity,
so heat and lack of water bring
about the same condition in others.
The animal or reptile that hibernates,
or goes to sleep in cold weather, arranges
its body so that it will conduce
to the greatest warmth, while those
that estivate, or become torpid in warm
weather, place themselves in positions
that show that they want all the coolness
the climate will permit. The tenric,
a tropical animal, carnivorous and
insectivorous, becomes torpid during
the greatest heat, and lies on its back
with its body drawn to its greatest
length, and its limbs spread wide apart.
Snakes estivate in the South, all kinds
together, just as snakes hibernate in
the North, but instead of rolling themselves
in great balls, as the northern
snakes do, they lie singly, and stretched
to their full length.</p>
<p>Want of water will cause the common
garden snail to go into a state of
the most complete and curious lethargy.
This is the snail of the genus Limax,
not the larger one of the genus Helix.
In the latter the phenomenon of hibernation
is especially remarkable. In
November the snail forms just a soft,
silky membrane across the external
opening of its shell. On the inner surface
of that it deposits a coating of
carbonate of lime, which immediately
hardens the gypsum. This partition is
again lined with a silky membrane.
The snail then retires a little further
into the shell and forms a second membranous
partition, retiring again and
again until there are six of these partitions
between the snail and the lime-coated
door at the entrance of the
shell. In the recess behind all these
partitions the snail lies torpid until May.
All this time it lives without motion,
without heat, without food, without air,
without circulation or the exercise of
any of its functions. If this snail is
prevented from hibernating for several
seasons by keeping it in a warm room,
it will gradually waste away and die.
A case is known where several snails
of this genus were shut in a perforated
box without food or water. They retired
into their shells and closed them
with a thin membrane. They remained
so for three years, but revived when
put into torpid water. They had been
driven into torpidity by drought. The
blood of this animal is white.</p>
<p>It may be of interest to state in connection
with these animals who pass
half the year, or less, in sleep, that
there are several species of fish, reptiles,
and insects which never sleep during
their stay in this world. Among fish
it is now positively known that pike,
salmon, and gold-fish never sleep at
all. Also that there are several others
of the fish family that never sleep more
than a few minutes during a month.
There are dozens of species of flies
which never indulge in slumber, and
from three to five species of serpents
which the naturalists have never been
able to catch napping.</p>
<div class="poetry-container">
<div class="poetry">
<div class="verse">Apollo has peeped through the shutter,</div>
<div class="verse indent-2">And awakened the witty and fair;</div>
<div class="verse">The boarding-school belle's in a flutter,</div>
<div class="verse indent-2">The two-penny post's in despair.</div>
<div class="verse">The breath of the morning is flinging</div>
<div class="verse indent-2">A magic on blossom and spray,</div>
<div class="verse">And cockneys and sparrows are singing</div>
<div class="verse indent-2">In chorus on Valentine's day.</div>
<div class="ar">—<i>Praed.</i></div>
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<hr class="chap" />
<p><span class="pagenum"><SPAN name="Page_86" id="Page_86">[Pg 86]</SPAN></span></p>
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