The Mitchell capital. (Mitchell, Dakota [S.D.]) 1879-1918, 1905-07-07
ORGAN OF SIGHT
IN ANIMAL WORLD
Wonders OF the Eye as Ii o
in the Lower
Orders.
TWO EXTREMES OF SIGHT
The Power of Vision in the Eagle q
Marvellous, Equalsd Only by the
Woodeock, Whils Snakes
Can See but Little.

New York Evening Post: There wan
certainly a time long ago when living
creatures were not blessed with eyes
In the creatures now living upon the
earth we may trace q series OF eyes,
from the highest and most efficient tot
the simplest dot of black pigment. The
eye OF the eagle may stand for the
first and the eye-spot OF the amphi-
oxus or the eight-sense germs of q
jellyf1sh for the other extreme OF the
series.
The an1phioxus is a little worm orr
fish-like creature which most OF thoi
time lives buried in the sand OF ouri
seashores. He is interesting n im-l
portant out of all proportion to hisi
size, two inches, for he is n of thel
lowliest creatures to be honored with
a backbone, the class mark Of alls
higher animals. He has no skull and
no BRAIN, but near the front end Of the
thin thread of nerve (the foreshadow-:
ing of our spinal cord) is a tiny black
dot. BY means Of this he distinguishes
light from darkness. which is all his
simple life requires. Let us not for,
get the position CT this single, most
primitive of eyes-in the center Of
creature had one.
The Jsllyfsh.
The eye of a jellyfish is SO PRIME
tive that we can hardly say whether it;
sees or feels. That is, when q floating
jellyfish begins to sink below the sur
face of the water as the shadow Of
an advancing ahip falls upon it it is
probably affected by the sensation OF
darkness, but perhaps the pressure OF
the onrushing wave has something to
do with 1t.
II We would see an eye which has
0Pfyy011v haan nxy01yyoI4 %r0~o ~~1 ;l.~
that Of amphioxus let us examine the
head Of a lizard. Disregard for a time
his two bright eyes, one on each side
Of his head, and look directly down on
the center of the skull between them.
Here we will n an oddly shaped
scale marked with a little depression,
and this is, indeed, what is left of our
Cyclopean eye IN the tiny sand crea-
ture. Lizards doubtless derive very
little benefit from 1t, as the nerve lead
of their ancestors it must have been
of great value in detecting the pres
ence OF enemies from above. In all
creatures above lizards this third me-
dian eye (called the pineal) Is found,
a annsi g no use whatever; the
great importance 1t nee was. In a
chick In the early stages of incubation
this y is very considerably devel-
oped. while yet the paired eyes are but
seems to realize that the old regime
has passed-that the little bird will
need other more modern eyes, and the.
two side eyes begin to develop with,
wonderful rapidly, and soon catch up.
with and distance the Cyclops eve.
whose early start ends only in promiss.
The Third Eye.
A horse, a bat, a mole, a monkey.
a seal, all have a trace Of this third
eye, n when we put a finger on the.
soft spot" Of h head of a tiny baby
we realize h wonderful import Of 1t
proach Of this same third eye to the
surface, striving as 1t has done in SO
many lower creatures to push its poor.
imperfect lens to where the light can,
act upon IT. But the old ways have,
blue eyes look out at You and the
world and see all that is necessary for
its life and needs.
We car hardly imagine anything
more terrible than the loss OF our eye-
sight, and yet there are many creatures
in the darkness Of caves and under-
ground tunnels or to roam only at
night, when their eyer are useless, and
by lack Of use these organs have de-.
generated to mere specks. and in some
cases the skin has grown completely
over them. Thus we find blind fishes
I'M lizards II dark caves and blindf
ants and moies all but blind in their
dark subterranean homes. Certain
bats, too, have but tiny dots for eyes,
and depend chiefly upon their acute
hearing and some sense by which they
can feel the vibrations In the air.
Eye Of the Snake.
Snakes have but poor eyeSight, and.
like fish, have no eyelids. Their eyes
are covered with a thin transparent
shade, at noon n midnight, in an aw-
full, never-winking stare. We cannot
imagine how sleep can ever come to
such creatures.
Finally. let us turn to the snost per-
can read and write and do many
things by the aid of our eyes that are
forbidden to other creatures Of tho
earth, but this is because of the brain
behind directing the eyes. We can look
closely at the stars and we can watch
the actions Of a tiny dot of. life many
thousands of times smaller than a mote
of dust. All this we car do by means
OF the two magic tubes" the telescope
n microscope. But when the unaid-.
to shame. Observe an eagle writes
q noted scientist, soaring aloft until
he seems to US but a speck in the blue
expanse. He is f~ar-sighted, and, scam.
ming the earth below, describes an OBJ
$3.50 oo- u Skxp " .
lance. He prepares to pounce upon his,
quarry; in the moment required for
the deadly plunge he becomes near
sighted, seizes his victim with unearr-,
ing aim and sees well how to complete
the bloody work begun. A humming,
bird darts so quickly hat our eyes
cannot follow him, yet instantaneously;
settles so light as a feather upon a
tiny twig. How far off 1t was when
first perceived we do not know, but n
the intervening fraction OF a second
the twig has rushed into the focus Of
distinct vision from many yards away.
A woodcock teans through the thickest
cover as II 1t were clear space, avoid
ing every obstacle. The only things
to the accurate perception Of which
birds eyes appear not to have accom-
modated themselves are telegraph
wires and lighthouses. Thousands of
objects to their destruction
Politics Piekin' Up.
- - 800