Alexandria gazette. [volume] (Alexandria, D.C.) 1834-1974, 1859-04-11
NO. So.
MISCELLANEOUS BEADING.
HOW sRRpRNTs CRAWL WITHOUT LEG


TEE CAUSE E1PLAisED.-Although depri.
we'd Of feet, fms and other obvious members
for walking. the serpent glides on the earth.
ascends trees, or even directs its course
through the wster, with surprising agility.
and with graceful evolutions; yet the serpent
was cursed above every beast of the field,
and man, as if remembering the curse, turns
from the reptile with disgust and horror, or
seeks to effect its instant destruction. Let
us examine how all this is effected and first
as to the spinal column.
The numerous bones or vortebra which
form this chain, are united together by ball
socket artculations; or, in other words,
the rounded head Of each is fitted into a
cup like cavity in its predecessor, SO that
the whole column is chain of these joints
capable of the utmost mobility compatible
with the safety of the spinal cord enclosed
within. The articulatiOns can only he
moved from side to side, and their progress
by vertical undulations, as in many old
prints Of serpents, is anatomically impossl-
BILE.
So also it is impossible for the snake u
perform the feat which has been ascribed 70
him, when he wishes to 60 quickly down
the hill, for, according to an absurd story,
he is said to put his tail in his mouth, aud
roll himself down, being in the form OF
hoop. 1t is just as well to recollect the fact
that a snake cannot turn himself directly
upwards when held by the tail He can
wriggle famously from side to ride. butcer-
tainly not upwards. Hence it follows that
the best way to handle snake is to hold him
out at arm s length; in this position he can do
no harm.
But how, it will be asked, does the snake
continue To get along ON the ground 50 last.
as he has no perceptible legs or arms 10
help him, This is managed as follows;-To
each vertebra-and large snake has many
dozen yertebre--s attached pair OF ribs;
the small end of those ribs are not attached
to sternum or breastbone, rs in man, but 10
a single scutum or scale on the abdomen by
means of slender cartilage and set of
short muscles. 1t is ON the points of these
ribs. which may he compared to the legs OF q
millipede. that the snake rests. and they act
in progressive order, just like the legs OF
that creature, each pair bringing forward The
plate or scutlm to which it is attached
This row Of scuta may thus be regarded as
one ample foot Sir f. Home, in his Com
parative Anatomy" gives an account OF the
muscles which. arising from theribs, give mo-
ton to the scuta. lie observes, that the rib
in the snake performs two functions; the up
per halfisc ncerned in respiration, the lower
in iOcomution.
Ifa snake be allowed quietly 20 crawl over
the hand, the progressive movement OF the
ribs may be easily distinguished; and also
if it be watched while crawling over any
raised edge las the back of book re-
auiring the firm application of two or three
scuta in succession, as the body glides over
it.
If you put a snake on bit of plate-glass
he can get no hold with the scuts, and he
comes powerless.
Snakes are often in the habit of climbing
trees, and we see them represented in en-
cravings, particularly in old pictorial Bibles
where the serpent is seen tempting Adam
and Eve. and in stuffed specimens in muse
ums, as coiling their bodies round the bran
ches, in rork-screw-like folds. Now the
snake when alive) never does this; it sim
ply glides up, the whole body extended in
straight line, clingipg by means Of the tip Of
expanded ribs, with the scuta attached, as
has been explained Mr.. Gros, tells us that
"the black snake in Jamaica will allow the
greatest part of his body ~ hang in the air
and thus remain still while little more than
the tail retains its position by clinging
straight not splrally, and not half round 1t
but longitudinally along i'll to the upper sur
face Of branch; and it will often pass freely
and gracefully from one branch to another at
considerable interval, projecting its head
and body with the utmost care across the in
terval." The motions of snake in tree are
beautifully easy and free, and convey tho
impression that the reptile feels quite at
home among the branches.-BucklaWds Cu-
riOsifjes of Natural HIstOyv