Decorah public opinion. (Decorah, Winneshiek County [Iowa]) 1895-1928, 1895-11-22

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! eyes. In many of such animals, how
| ever, the eyes have been overgrown by
the skin, so that these eyes would be
useless for vision, even if the animal
should come from it's subterranean
nome to the light of day. The same
is true of the mole and mouse tribes.
indeed, all the vertebrate animals have
Two eyes, whether they use them or not
NOT all animals have these two eyes
symmetrically placed in the head, one
on each side. Certain fishes which ap-
parently swim on the side such as the
turbot, have both eyes on the side-the
dark side OF the head. That this is not
que to simple twist of the head was
demonstrated by Professor Steenstrup
more than twenty years ago.
AT times, by what is termed arrested
development, animals, and even human
beings, appear as cyclops, or having
one eye only. But who ever heard of
third eye in man or beast? And yet
recent researches prove that man and
all Vertebrates seem to possess the ru-
dlments Of third eye.
This discovery is not only very inter-
estlng, but also remarkably instructive,
since the rudimentary third eye Of man
mas, by one of the most noted philoso-
phers OF modern days been looked upon
as being the seat ns the soul.
AS organs by proper use develop in
strength and perfection, so they be-
come weak by lack Of use. If for many
generations an organ should remain
without use, it's structure in time be-
comes simpler and more imperfect II
such a process continues throughout
ages, the organ, by constant disuse, will
become reduced to q mere rudiment of
what 1T was in the species using the
same. Thus, species of birds that only
walk and run, but never fly, have only
rudimentary wings, as the ostrich,
while in the eagle and the albatross
the wings are seen in a state of per-
fection
Now, in closely examining the skulls
OF certain lizards, it was found that near
the top of the head, under the dark,
Opaque skin, and often in the very bone,
an almost perfect eye exists, though no
ray of light ever could reach it.
This eye shows a crystalline lens,
retina of very complex structure. and
an optic nerve-in fact, all the essential
parts of perfect eye But being COW
cred by the opaque skin of the animal,
it is absolutely useless.
II this optic nerve is traced to the
brain, it is found to connect the eye
with the so-called pineal gland of the
brain. This pineal gland is, of course,
in no sense of the word real gland,
but definite portion of the nervous
tissue of the brain, invariably located
just back and partly over the cerebrum,
and in front of the rounded brain-mass
which generally is considered to cor
respond to the corpora quadrigemina in
man.
This third eye of the spotted lizard is
called the pineal eye. on account of the
nerve connection of its retina with the
pineal gland.
Now, while in certain lizards this
highly developed eye is useless because
it is covered by Opaque skin, and in
even uOSPiy iuiDCuuCu III DOUe,
it would seem probable that in an
earlier stage of development this pineal
eye was not rudimentary, but in con-
slant use. A very slight modification
would accomplish this-namely, the
of the skin covering of the
eye. This is exactly the condition of
the normal eyes in reptiles to-day; the
skin covers them, but it is transparent
where it passes over the eye.
In the skulls of some of the gigantic |
reptiles of the earlier age of this globe !
psychologists have long ago found a |
large, round perforation. Probably this |
was the socket of the third or pineal |
eye of the ichthyosaurus, the plesiosau- /,
rus and the labyrinthodon.
But a much more important conclu-
sion must be drawn from this discov- |
that in all vertebrates. |
even including man, the traces of this |
third eye remain to-day. The pineal |
eye of lizards being connected with the
large pineal gland of the same, it |
would seem that the pineal gland itself |
is but the nerve center of optic thalmus
for this third eye. In all reptiles and |
amphibia the pineal gland is large; so
1t is also in fishes.