Evening star. [volume] (Washington, D.C.) 1854-1972, 1913-03-30
BIZ J. EARL CLAUSON

the statocyst is indicated by shallow pit
of the outer skin. A minute pore, barely
large enough to admit the point of a pin,
opens through this into a chamber on the
floor of which are four hundred, more or
less, tiny hairs, each provided with nerve
element. Some of the hairs have bent
shafts, some are threadlike, and to the tips
of many are glued great many fine grains
of sand.
The chamber is filled with water. When
some disturbance of the element in which it
lives, or the pull of gravity, disarranges the
Holsters equilibrium, the swaying of the
body causes the little hairs to trenble, or
the grains of sand to rattle over them, and a
warning is sent to the whole nervous system
to guard against an upset.
THERE is no more remarkable phenome-
! non of invertebratel life than the power of
the lobster and its kind to amputate limbs at
will and develop new ones. 1t often occurs
that by the sacrifice of claw the crustacean
can escape with its life from an enemy; and
it never hesitates to make the sacrifice. 1t
is as if man whose foe had caught him by
the hand was to drop his entire arm at the
shoulder socket, confident that within short
time a new arm would replace the one that
was lost.
This process, which is known to science
as autotomy, is accomplished through re-
fex muscular contraction. Nature has es-
tablished a definite breaking plane, where
the amputation always takes place. While
the loss of any considerable amount of It's
sue in vertebrate life entails severe shock,
the lobster may lose one-half its weight, or
even more, by the self amputation of both
great claws, without suffering more than
temporary inconvenience. There is little
loss of blood and within few days new
tissue of the kind destroyed makes its ap-
pearance at the place of the wound, and the
work of regeneration is begun.
1t might be thought that, since Holsters
possess so wonderful a power of restoring
lost parts, the fortunate individual who kept
a thankful of these crustacea need never re-
place his stock; that, confident that the loss
would be made good, he could collect a few
great claws whenever he desired to make a
salad. theoretically such is the case. The
obstacle to practical execution of the plan
lies in the length of time needed for the de-
velopment of new parts. HOLSTERS are re-
stricted in their growth by an inelastic shell,
which when the body within demands larger
quarters is cast off to give place to a new one.
Molts in the adult lobster may be as infre-
quent as once in two years, and the regen-
Grated member may wait upon two or more
moltS before attaining the size OF the lost
one. A large number of Holsters would there
fore be required by the man who sought
to have steady supply without sacrificing
life
Since so long time is needed for the re-
production of lost parts, it may easily be
suspected that the lobster itself is an animal
of deliberate habits of growth. In its first
year it molts from fourteen to seventeen
times, and attains a total length of not to
exceed three inches. To reach marketable
state-ten inches-it must mott from
twenty three to twenty five times, process
that requires five years for the male and a
year and half longer for the female. These
figures are subject in some degree to the
qualifying influences of water temperature
and food abundance.
AS the lobster grows older, the periods be-
tween molts lengthen, following the uni
versal law that youth is the time for growth.
Whether there is for the lobster, as for land
animals, an age limit for increase of size,
has not been definitely determined. 1t is
suspected, however, that the melting proc
ess is continued throughout life; since it is
essential not alone to growth, but to escape
from troublesome parasites that attach
themselves to the shell. 1t may be that
natural death comes to the lobster not di-
rectly from old age, but from weakness,
which prevents it from casting its heavy
armor, rusty from use and SCARED in many
q conflict