The daily national Whig. [volume] (Washington, D.C.) 1847-1849, 1847-10-23


The whole type of radated animals may be divided
into three classes the poyps, containing the coral
| the jely-fshes, and the star-fshes.g ~
In their external appearance these classes do not
differ very much.
Here the lecturer directed the attention Of hs a,l-
ditors to several Illustrations OF the various elasses Of
radiated animals
But In their internal structure they differ widely
All polyps have one single cavity in which all the
organs are contained; and al these organs consist only
OF large stomach and some groups of eggs arranged
around the stomach. BY means Of these tenacles
they seize on their prey. In the centre is the mouth
Here is the general substance Of the body formed Of
fieshy material, its walls being vertical lines. This
animal is very softin its substance II is feshy ind
when touched contracts suddenly II closes its ten
taces entirely when touched its mouth is also con-
tracted in that case and assumes spherical form,
showing no trace whatever of the beautiful external
appearance which you see represented in the draw
ing The vertical folds which are here scarcely per-
ceiyed, become marked and distinct
If such an animal be cut vertically, you will see
that 1t contains one large cavity with wide open
ing below. Through that opening You enter another
cavity Tho walls Of these cavities are folds which
the partitions running TO the periphery Some
ofthese folds will not run to the stomach, and form
only subdivisions of the principal partitions Be-
tween the two cavities there is, MS have said a
wide opening This Structure is common to all po-
yps The organization Of this class is pretty well
known now though il has not been long studied with
minute altenuon' ms augmented knowledge Of
poyps Is owing 70 the Efforts OF the naturalists ofthe
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aii''i''s, WI" pe seen tha' 'ns organization Is very
o 'eh ie'e 'race me animal functions
W uen nv aoWes' 'onu''ion, TOW 10 uiese animals
I'VE Ing Ing iooai - seized ~ thesc tentacies the
"ho,e suiuce VI 'e 'entaces Is covered win micro
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t ..'.t ~, u 1no .en'a''eS coYcrep ~ u
"eie WIN a''u .neso nars are III constant IN
u ~, =. inherent alecuons continuous
aurren. n wafer y inns maintained oy these minute
aPPehuases Iiere again. IN the opening, thesc vio-
ratory ciila are constantly In motion; and In the in
ternai cavityihere are also seen vibratory ella NOV
ing constantly They are not under the control Of
the nerves-not under the control Of the will. They
move necessarily From the moment the animal
escapes from the egg and even when within the egg,
they are in motion. During the rest OF the animal,
us Wen as during the more active periods OF Its exist
ence, these unwearied organs are at work
Now, II Is owing TO the action Of these ella that
minute portions Of organic matterare introduced into
the anlmafs mouth. considerable space OF several
nches IN dianeter Is swept by these tentacul9 All
he niue partcies-imperceptible to the eye-of an
nai matter OF decomposed vegetable matter, Shells
ana SO on are mus Drought into the mouth and thus
1000 Is supplied to the animal incapable 6f moving
or running after other prey This is the mode with
which Nature mas provided for the sustenance of
these animals.
But beside this mode Of alimentation, these ami
mails can contract their entaces and seize upon large
prey. Polypsiof a few inches in diameter will seize
fish, surrounding it with their tenacles and intro
ducng 1t into their mouth, after which II is dgested
very rapidly. Now this mode Of alimentationis per-
formed IN a very interesting way. The tcntacle Of
such polyp Is q very complicated structure. had
an opportunity lately to study its microscopic struc
ture and nave found that each tentacle, examined
under considetapie microscopic power, Is tube
whose Walls are formed OF longitudinal muscular H.
,.N.t t--9i .Ii' " - 'S ''''-eso ''i1
higher animals ny their contraction these fbres
eau shorten '''e eh'ace ~ e airecnons; or II excl
ea ony On o.e sue 'cy VIII curve on mat SIDE
ieii aaili' .he'e u,c oilel circnar npres around
wv "noe 'uoe, unu 'iese pun 'ae ,ehtaceln success
'io's 40 ~ e'1nsa'e "e,h IN TOUT .nies us
usuai s nus '"e uiiiiu' - enabled 10 selze
upon Aisei pies. M,.5
Such is the manner IN which the iood Is introduced
into the internal cavity. The cavity Is sac, and
even q sac which is open Mt both ends. But then
the ends may be contracted and shut at the animals
pleasure When the whole animal is contracted both
these openings Of the stomach are shut and when
the animal nae filled its stomach with food the lower
opening OF the stomach - closed. But as soon as
the food Is within that cavity it comes IL contact
with some secretion probably similar to the bile or
the salivary fluid Of higher animals AT all events,
il is subjected to the influence of some agent the
character Of which has not vet been asccrained but
should be ascertained as the animal is yery common
on the shores of this continent. Digestion is rapid
in these animals. Even shells are speedily assmi
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