Evening star. [volume] (Washington, D.C.) 1854-1972, 1880-03-13
HybernatiOn.

MOSI beasts 90 not hibernate, because they
have the power of keeping up uniform body
temperature in spite OF the cold of winter. In
the d0rmOuSe, marm0t, and many allied FORMS
however, as also III the hedgehog and in bats
We do find this winter sleep to occur. The lower
animals, such as reptiles, frogs, and eftS, many
fishes, spiders, shellfsh, and worms, also enter
into this state; while yet lower creatures such
as infuSoria and rhZopodS, protect themselves
By excretfng, and forming a structurelesS,
spheToidal coat or ''cyst." In preparing to hi
btrnate animals seek secluded and sheltered
hooks, or 6urrow In the dry ground or In mud,
the bark Of trees There they fall into
sleep (either uninterrupted or in
tesrGpted da by or intervals o rails of activity
tu1e and consequent length of winter. During
this sleep the body-heat of warm FLOODED ami
mails falls greatly ,aS respiration and circulation
take place very gently and slowly. The nutrl-
fat Of the body generally considerable at the
commencement OF hibernation) being used up
in the process, unless occasional awaking has
given an opportunity for feeding. An annual
period OF repose, analogous to Information, also
takes place during the dry season In many trop-
ical anlmals-as In many reptiles, frogs, and
of Madagascar, which has superficial resem-
blance to the hedgehog, also resembles it as to
its annual torpor, aad certain lemuroidS (of the
genus Chedogateusl which inhablt the same
Is sud, seem also to prepare for the torpor of
the dry season by storing up q quantity OF fat
in heir tails which, IL is alleged disappears b;
the time that the period OF activity has re-
tuIed. Parallel with the periodic rcpOSe of
animals Is the winter inactivity OF very many
planS which in temperate ATTITUDES such as
our OWN drop their leaves, or, if herbs, die
dOHn TO shoot forth again with the advent OF
spihg. During this time the SIP retreats from
the surface, and the processes OF life come al
most TO saGd-stil, 10 be renewed with a
IapiGty and suddennesS not inaptIy termed a
burnt o. vegetation" at period which varies
according to the species. The annual torpo
, Of animals Is a pTolongation for weeks or
1cr moths OF that process, so familiar yet
so MYSTERIOUS, called sleep. During 1t the
: iundiot OF HE are slackened In their
operations. and the refrcshment which sleep
probes Is not due to any accelerated nutrition,
but 10 temporary cessation OF the wear and
tear Oactiyity. The immediate cause of sleep
is not et satisfactorily known. 1t is intimately
connected with some conditions OF the nervous
centet. and IL has been supposed that its lmme-
diate huse was diminished quantity of blood
IN th,braiD, but as yet this view has not been
adeqhtely supported by facts. During sleep,
the 6bS are generally relaxed, and the position
-ssrped by the body is often that which the
emtf!o had taken before birth. The nervous
ceneis are also more OF less completely cut Off
iron external influences, the avenues OF special
seSe being more or less obSCructed b. the
Vsition assumed by the body, by the closure
the eytIds, &C Not only is this the case,
nut the very stimuli received fail to excite
fsponse unless they are of much more than
ordinary intensity. Indeed, when exhaustion
pas been very great, and sleep long deferred,
ttimuli are powerless, and the access of sleep
W
the rack. Ordinarily. the advent OF darkness is
The signal for sleep, but in nocturnal animals
fhe period OF daily repoSe Is Inverted AS the
process or refreShment, induced by sleep
becomes more and more perfected a
slghter and slighter stimulus is alone
needed to awaken the sleeper, till, at last
the mere changes OF organic life suffice to
arouse the nervous centers to their wonted ac-
fivity. But although these cenJers are during
sleep more or less deprived or commerce with
the external world. they still maintain certain
activity, as is evidenced by dreams which often
ELECTS sounds and slight movements even in
The lower animals e. o., in dogs as well as In
ourselves 1t may, indeed be that we always
dream when asleep though our dreams are
generally forgotten Immediately on awakening
This question cannot be absolutely determined
though on the whole IL seems more probable
that II Is only in imperfect sleep that we dream
That our nervous centerS are not entirely cut
on from the external world is proved py our
dreams being often Influenced by sounds
merce with the external world must take place
In the abnormal sleep OF the sleep walker who
may so wonderfully adjust his movements to
varied conditions around him. A mere local
lethargy occurs in hypnotism, when the patient
not only sees, hears and feels but replies to
questions and exercises his Imagination in re-
Spouse TO suggestions with the greatest readi-
ntsS while remaining utterly paralyZed as re-
CARDS his voluntary actions Plants, since they
have no nervous system, can have nothing real
~ similar TO the sleep OF animals yet many
plants assume special positions as to parts or
their frame with the approach of night FOIL.
age leaves will fold themselves ana flowers will
close, movements which as vet have received
no adequate explanation as Will appear when
beings to one another.-.S. G. MtrdI1, IN C0nteR,
JOFU5U RPriplr.