Green-Mountain freeman. [volume] (Montpelier, Vt.) 1844-1884, 1875-07-21
Che family Circle.
SpOnges.

On examination of Il sponge skeleton. i.
will be seen that the porous surface is finer
and of closer texture than tho INTERIOR
that there are large apertures scattered
indiscriminat over the surface, and be
tween are much finer openings, covering
the complete outer surface of The sponge.
The latter are called pores. and serve IL
channels of entrance to the water, which
after circulating through the body by
means of the tortuous and branching ca
nails which make UP the inner skeleton
passes out ut the inrger openings. Thes
chimney-like apert'lreS are called osc1tia.
but the name is Il msnomer. for they are
in reality. vents. They vary in number in
the different species, and are sometimes
reduced t. single one BY what fore
the water is made to circulate through the
sponge mass is not definitely known
Some have attributed it to virbratile ellie
planted within the porous canals which
bv their motion, create Il circulation in the
water. q. hers a~crhc it to the principle
If o>mo-is. by which membranes Of all
animals and many oher porous subSt tnct>
transmit fluids and gases according to
heir density an power To act on the trans
hitting substance
When obtained for commercial purposes
the animal matter can he removed bv soak
me- it for Il long time in silt water and then
after it is rotten bv this misunderstanding
il out. This leaves the horny skeletons
lust rs we Use them.
The finest spo gtS Of commerce come
| from the Mediterranean Sea. Our BATH
sponyes are doubtless from this locality,
but the coarscr sponIe> We see most com
monty come from the coasts of Flprid or
he Bah ,mt I>llnds. SpungeS are fpun
| tbundtntlv in tropical waters generally.
md perhtl,s nowhere more ;tbund mt tn IN
n the >r,> of tie Australian Islands, Tm Y
II tdutllv decrease in number, towards the
colder lttitudr> TIL they become entirely
extinct. They vary much in shape. som,
re beautifully shaped like a vase, other
ne semi cylindrical others nearly fit like
IN open fan; some are hrtnchtd like tllt
open FINGERS Of Il hand. and ave called glov,
~ponLc>. and in other, III, Sc branches seen
t. be reduced to only one. which is sh tppc
somewhat like u club These different
SHAPES may belong to one species. and I'll,
Il tftrrnr e are due 50 for rs known to III,
fact that the ii It mentioned are found il
Itep water. and lh-v grade. in the ord,i
described. up To the last. which grow il
much shallOwtr water.
Spunge> are not confined To recent seas
though de commercial ones are not know
To have existed earlier, b.clr,>- the kcrt
to-e matter furnishes hardly favorable con
iii ions for lrtritaction. In he oollte IN,
halk f"rmatlon>. p mes cont ,lnlnE film
V ~picult> Were very abunl mt: and il
most of the etrli"r form ttjun~. larr
SpnnTeS con'ajnny calctrtous Spiculr
hound,l. These very closely r,.>rmhl
cOral>. AMI have been mistaken for then
hv some of our best gcolo.i> The >li
'ul;e or nee,llt>hap'd particleS. which al
often microscopic in size. are not thrown
N without order, bu ar, arranged 10 : ~
port the skeleton. The horny sponge, IL
not >ecrere or deposit >piculcs bat III :
are sometimes foInd within the skeleton
n broken and di>ur,e Ell form, whc
shows ,h,v were ken in from without.
There i IN elastic sponge ~ it is called
that is somewhat used rs a substitute fo
rurlrd hair in stutfiny bed cushions, G.,
seats, etc. but this is an entirely ditftrtn
thing from the sponge of commerce. BE
fore it was used for this purpose il WIS
worthless sea grass. growing abundant
among coral> in rather Sh ,lluw water.