The Camden chronicle. (Camden, Tenn.) 1890-current, 1903-05-22

EVoLUTloNlsTs CAN TELL US
NOTHING or THEIR ORIGIN.


Some That Weigh q Ton-Faets About
Only Animal Who Needs No Strong
Baekbone-Well Developed Senses,
Thelrs-Eggs Hatch by Themselves.
A turtle. waddling his solitary way
along some water course. attracts lit
tie Interest outside OF his clumsy, gro
tesquo shape, yet few who look upon
him are able to give, off hand. even q
bare half dozen facts about this hum
bic creature. And II they could give
any, their information would be limit
ed to two or three usages his body Is
put to-soup and mandolin picks
also combs.
There are about two hundred differ.
ent kinds Of turtles. and they live in
all parts OF the world. except in very
cold countries. Australia has the few
est, and North and Central America
the greatest number of species. Eyo-
lutionists can tell us nothing OF their
origin, for as far back in geological
ages as they are found fossil Ga mat
ter of little over ten million years.,
all are true turtles. not half turtles
and half something else. Crocodiles
and alligators, with their hard. leath
cry coats, come as near to them as
any living creature, and when we see
a huge swapping turtle come out of the
water and walk about on land We can
not but be reminded of the fenow with
the armourer back.
Turtles are found on the sea and on
the land. the marine forms deserving
the name of turtles. more properly;
tortOises being those living on land or
in fresh water. but we will use the
name, turtles, as significant of the
whole class The most natural way of
classifying these creatures is by the
way the head and neck are drawn
back under the shell; whether the
head is turned to one side. or drawn
straight back, bending the neck into a
letter S shape.
The skull of the turtle is massive,
and some have thick false roofs on top
of the usual brain box.
The house" or shell Of a turtle is
made up of separate pieces of bone,
central row along the back, and others
arranged around on both sides. These
are really pieces of the skin of the
back changed to bone. Our ribs are
directly under the skin of the back,
and If this skin should harden into a
bonelike substance, the ribs would lie
fiat against it, and this is the case
with the ribs of turtles. So when we
marvel that the ribs of a turtle are on
the outside of its body, a second
thought will show that this is just as
true of us as of these reptiles.
This hardening of the skin has
brought about some interesting chang
es in the body Of the turtle. In all the
higher animals from fishes up to man
a backbone is of the greatest impor-
lance, not only to carry the nerves and
blood vessels, but to support the en-
tire body. In turtles alone the string
of vertebrate is unnecessary, the shell
giving all the support needed. So as
nature seldom allows unused tissues
! or organs to remain, these bones along
the back become, in many species, re-
duced to a mere thread.
The pieces of bone or horn which
go to make up the shell, although so
different in appearance from skin, yet
have the same life processes. Occa-
sionally it mouths or peels, the outer
part coming off in great flakes. Each
piece grows by the addition of rings
of horn at the joints, and Cike the
rings of tree) the age of turtles, ex-
cept very old ones, can be told by the
number of circles of horn on each
piece. The rings are very distinct in
species which live in temperate eli
mates Here they are compelled to
hibernate during the winter, and this
cessation of growth marks the inter
walls between each ring. In tropical
turtles the rings are absent or indis-
tinct. 1t is to this mode of growth
that the spreading of initials which
are cut into the she'll is due, just as
letters carved on the trunks of trees
in time broaden and bulge outward.
The shell has the power of regen-
GRAFTON, and when a portion is torn
away or crushed the injured parts are
gradually cast off, and from the sur
rounding edges, a new covering of
horn grows out. One-third Of the en-
tire shell has been known to be thus
replaced.
Although so slow is their locomotion
~ ootiove +,,rt1ae howe vUol1 laval