The Portland daily press., 1890-09-04
TnE LIFE OF A SPONGE,
. its Development from Particles Of
P(otopIaSn,
ILond0n Illustrated News.

First Of all we may note that q sponpe
IS we know it in common life. is the
horny skeleton or framework which was
MADE h al whicA Supported the liv-
ing parts. These living parts consist of
minute masses of that living jelly to
which the name of protoplasm has been
applied. This, in truth, is the universal
matter of life. 1t is the one substance
with which life everywhere is associated,
and as we see it simply in the sponge, SO
also we behold it (only in more complex
guise) in the man.
Now the living parts of this dried,
castaway sponge We're found both in its
interior and on its surface. They lined
the canals that everywhere permeate the
sponge like substance, and microscopic
examination has told us great deal
about their nature. For whether found
in the canals of the sponge themselves or
imbedded in the sponge substance, the
living sponge particles are represented
eachb by neutrality-suspicious. of proto-
plasm. So that the first view would have
you take of the sponge as living mass is
that it is colony and not a single unit.
1t is composed, in other words, of aggre-
gated masses of living particles which
bud out one from the other and manufac-
ture the supporting skeleton we know as
"the sponge of commerce" itself.
UNDER THE MICROSCOPE.
Under the microscope these living
sponge units appear in various guises and
shapes. Some of them are formless, and,
as to shape, ever altering masses, resem-
bling that familiar animalcule of our
pools we know as the ameba. The
members of the sponge colony form the
bulk Of the population. They are i'm
bedded in the sponge substance; they
wander about through the meshes of the
sponge; they seize food and flourish and
grow; and they probably give origin to
the "eggs" from which new sponges are
in due course produced.
More characteristic, however, are GER
tain units of this living sponge colony
which live in the lining membrane of the
canals. In point of fact, sponge is a
kind of Venice, certain proportion of
whose inhabitants, like the famous queen
of the Adriatic herself, lived on the
banks of the waterways. Just as in
Venice we find provisions for the deni-
zens of the city brought to the inhabi-
tants by the canals, so from the water,
which, as we shall see, is perpetually cir
culating through sponge, the members
of the sponge colony receive their food.
Look at sponge fragment. You per-
ceive half dozen large holes or so, each
opening on little eminence, as it were.
These apertures, bear in mind, we call
oscula. They are the exits of the sponge
dominion. But close inspection of a
sponge shows that it is riddled with finer
and smaller apertures. These latter are
the pores, and they form the entrances
to the sponge domain. On the banks of
the canal you may see growing plenti-
fully in summer time a green sponge,
which is the common fresh water spe-
cies.
Now if you drop living specimen of
this species into bowl of water, and put
some powdered indigo into the water,
you may note how the currents are per-
petually being swept in by the pores and
out by the oscula.
IT'S NoURISHMENT.
In living sponge this perpetual and
unceasing circulation of water proceeds.
This is the sole evidence the unassisted
sight receives of the vitality of the sponge
colony, and the importance of this cir
culation in aiding life in these depths to
be fairly carried out cannot readily be
overestimated.
Let us now see how this circulation is
maintained. Microscopically regarded,
we see here and there, in the sides of the
sponge passages, little air chambers or
recesses, which remind one of the pass
ing places in a narrow canal. Lining
these chambers we see living sponge
units of type different from the shape
less specks we noted to occur in the
meshes of the sponge substance itself.
The units of the recesses each consist of
a living particle, whose free extremity is
raised into a kind of collar, from which
projects lashlike filament known as
fagellum. This lash is in constant
movement. 1t waves to and fro in the
water, and the collection of lashes we
see in any one chamber acts as veri-
table brush, which by its movement not
only sweeps water iii the pores, but sends
it onward through the sponge, and in
due time sends it out by the bigger holes
or oscula.
This constant circulation in the sponge
discharges more than one important
function. For, as already noted, it
serves the purpose of nutrition, in that
the particles on which sponge life is sup
ported are swept into the colony. Again,
the fresh currents of water carry with
them the oxygen gas which is necessity
of sponge existence, rs of human life;
while, thirdly, waste matters, inevitably
alike in sponge and in man as the result
of living, are swept out of the colony and
discharged into the sea beyond. Our bit
of sponge has thus grown from mere
dry fragment into a living reality. It
is community in which already, low
as it is, the work of life has come to be
discharged by distinct and fairly special
lied beinos - 1919 60