Wausau pilot. [volume] (Wausau, Wis.) 1896-1940, 1905-07-25
NATURE Is A KIND MOTHER.
CURIOUS METHODS BY WHICH
SHE MEN0S ANIMAL INJURIES.

The Earthworm Grows a New Half
body to Replace the One Drowned
by Robin for 8reakfast-Lizards
Can Grow New Tails.
How many weak and timid crea-
lures there are in the world, with
neither teeth and claws for their pro-
lection, armor for their defense, nor
speed with which to escape their enc
mics, One can hardly understand
why they have not all been killed and
eaten up long ago. Nature is, how
ever, kinder to these poor animals
than she seems; for if she has left
them defenceless against attack, she
has given them marvellous power
of recovery from injuries.
When a tiny lizard has to scamper
for his life ia search of a crack in
the rock, he often has so close a
CALI that his pursuer snaps off his
tail just as he whisks into safety. A
loss like this would kill most larger
animals, but not the little lizard. He
simply waits round quietly until
new tail grows, and then is as well
off as before, except that the new tail
has a flexible rod of cartilage where
the old one had backbone.
If an earthwoTm happens to be re-
firing to his hole when q robin is
out looking for breakfast, there is
apt to be lively tug OF war between
the eater and the breakfast. Not in
frequently the bird gets the tail end
of the worm, while the other half
crawls away into safety. Not even
lizard could survive such treatment
as this, but the earthworm is, in abil-
ity to recover from injuries, almost
as much superior to the lizard as the
lizard is to us. He grows new half
body to replace the one which has
been devoured, and seems to mind
his loss no more than body minds
having his hair cut
There are, besides, some snail-like
water worms which quite Guido the
earthworm. If one of these chances
to lose his entire head, in a week or
so, sometimes in only four or five days
he grows a new one, brain, eyes,
and all, and is as we'll off as ever.
Even if hungry fish gets two bites
at him, so that he loses both head
and tail, the worm can patch himself
out with new members and go about
his business as before. They have
even been known to get divided into
two pieces about equal in size, and
each piece grow a new half-body, Sc
that there were two entire worms in
place Of one.
After this it will easily be guessed
that if the head end of the worm hap
pens to be split half way down he
will grow two new sides and become
Y-shaped with two heads. Or if the
tail end is split new sides grow and
a two tailed worm is made. Some
times one or two new heads develop
close behind the old one in the angle
of the Y. Indeed, the little creature
seems to have a sort of mania for
making new heads and tails wherever
he finds a chance. If, therefore, the
worm, after receiving several
wounds, manages to escape with his
life from the cuts which happen to
open forward, little heads grow out,
and from those opening backward lit
tie tails-no doubt greatly to his en-
barrassmelt.
But what of the cutoff heads and
tails? Do they make new bodies and
become whole animals again? Not
usually The severed head seems to
become confused, so that it does not
know what to do. If it lives it is
most apt to produce another head like
itself, and change into two heads
placed neck to neck so that they look
in opposite directions. So, too, the
severed tail, equally foolish, doubles
itself and becomes two useless tails
growing end to end.
But isn't this really quite impossi-
BILE? A head or a tail or even half
body cannot get food. If it cannot
eat it cannot grow; and that is all
there is about it. Well, it is true that
a fragment cdnHoC eat DuC sui 1t
can make the new part out of it's own
tissue. So the animal keeps getting
smaller as it becomes more nearly
complete, until, when the new part
is finished, the whole body may be no
more than the tenth part of it's prop
er size. The reconstructed animals
are, therefore, forced to begin life
over again like young worms. In
time, however, they grow up to full
size. When a head end makes new
head instead of a tail, or a tail makes
a new tail instead of a head, the lit
tie creatures must necessarily waste
away and die-From Nature and Sci
ence in St Nicholas.