New-York daily tribune. [volume] (New-York [N.Y.]) 1842-1866, 1847-10-20
which you see represented in the drawing Inc
vertical folds which are here scarcely perceived
ksco,,. m All "A and disrincf


inE below. Through that opening you eh'e' al p,
er cavity. The walls q these cavities are io'us
which are the partitions running 70 the periphery,
Some Of these folds viii not run % the SION -cD ~"
form Only subdivisions Of the pnncipsi ps',i'uns
Between the two cavities there Is as hs'c 80,
a wide opening. THIS structure u common 70 Al
polyps The organization OF this eiAs' - Pie"s
well known now though i has not oeen iols .'u
died with minute attention. ms ao@mehteu
knoxiefge q p0lvps 3 owing 20 the ehor'soi tne
uaturalists 81 the Exploring Expeatiioh 81 .nH
country under Captain " likes Applause a--
able contributions - this department o aura
History have also been made By Mr Dana Ms
work must always be a standard a1ihofiiy' zap
plnusel ,-,-
Ga entering into some more minute fetais OF
these auimas u vii be seen that TINS oiSAn@a'ioh
i very interesting. We can here trace tne AMI
ma functions 10 their lowest conHlilop- nov 40
these animals live The food Is seized by these
teotacles The Whole surface OF the teuiac.es Is
covered with microscopic vlbrstory ciha-httie'
soft projecting hairs g. minute as 10 De dscerni-
BE oflv under a microscope OF very considerable
power Unless you apply two hundred ana MI!
diametefs-which IS very considefaoe power
you can scarcely perceive these httie cliA- bu'
under such a magnify ing power yoa see the entire
surface Of these tentacles covered as We're VIII
hairs and these hairs are IN constant ince"abt
motion In different directions continuous
current OF water is thus maintained BY these
minute appendices Here again, IN the open
ing these vibratory ellis are constantly 10 motion
and ia the internal cavity there are also seen yibra
tory ella moving constantly They are MT under
the control Of the nerves-nOt under the contrO! 81
the will. They move necessarily. From the mo
ncut the snimAl escapes from the egg, ana even
when within the egg they are 10 motion. during
the whole period Of liie these cha DO not cease u
move They act b. day and night during me
rest Of the animal Is well as during the more &C
.fr. r.rtnfIs AZ existence these AIRED or
gsns are at work
Now. Il is owing 20 the action OF these ella that
minute portions Of organic matter are introduced
into the animals mouth. \ considerable space ol
several inches IN diameter is swept BY these ten
tcculn. All the lille psrticles-imperceptiole to
the eye--of animal matter OF decompOsed vege.a-
BILE matter shells. and 50 on, are thus brought INTO
the mouth and thus food IS supplied % the animal
incapable ol moving or running after other prey
This is the mode in which Nature hss provided Tor
the sustenance OF these animals.
But beside this mode Of a.imentation, these AMI
mails can contract their tentacles aud seize upon
large prey. Poyps Of n few inches in diameter viii
seize fish, surrounding It with their tentacss and
introducing il into their mouth after which II Is d
rested very rspidly. Now this mode OF alimenta-
ZION is performed ia very interesting way. The
tentaclc Of such polyp IS very complicated
structure. ! had an opportunity lately To study
It's microscopic structure, aud | have found that
each ten;sce, examined under considerable micros
copic power, - a tube whose walls are formed al
longitudinal muscular ibres hbres similar IN struc.
ture TO the muscles Of the higher animals BY their
contraction these bres shorten the tentscie In
All directions or if excited only one eide they
will curve u on that side. Then, again, there are
other circular hbres around the whole tube and
these pull the tcntace IN succession 50 as 10 elon-
gate II 10 them IN four times its usual length mus
the animal IS enabled 10 seize upon lsreer prey.
suchis the manner IN which the food is INTRO
...l ~ IL
81 nple sac aud even sac which Is open At both
ends But then the ends may be contracted aud
81 at at the animals pleasure. When the whole
animal Is contracted both these openings OF The
stomach are shut. and when the animal has filled
is stomach with food the lower opening OF the
stomach closed But as soon as the food within
thatcavity it comes 10 contact with some secretion,
urobsbiy similar q the bile the saiivary huid OF
higher animals At all events, It IL subjected 81
the influence Ol some agent the character OF when
has not yet been ascertaIned, but should be ascer
tanned. AS the animal Is very common on the shores
of this continent. Digestion is rapid IN these AM
mails Even shells are speedily assimlated, the
hard parts being rejected by the mouth, aud She
nices produced under the Influence OF the walls 81
the stonachs are ditfused into the lower cavity
The TODD is introduced into the stomach win
certain quantity Of water, so that tue food is
from the beginning mixed with quantity OF wa
ter but the moment the food has been dgested ~
the stomach il passes INTO this lower cavity and IS
there mixed with "A greater quantity a water
Now this dicested food begins 10 move IN the whOl"
cavity aud To- move between all these partitions D,
and the motion is produced IN way similar to that
OF the tentscles. These partitions hsvothe whole
of their surface covered with vbratory ella 50 that
the water containing the alimentary substance is
constantly moving between them. The refuse OF
the water escapes through the teDtacles. We have
here the digestive function as It were, combined or
mixed with kind Of circulation There is indeed
no blood IA these anlmals--no Nessels-nO respra-
ton proper. There is only one large cavity divided
into two the upper one digesting the food. and
then we have this digested food mixed with water,
and this fluid a. ain diilused throughout great
many smaller cavities In contact with the walls OF
the animal These walls absorb the huid like
sponge. aud the almentary portions remain within
the body of the animal, while the superhuous wa
ter escapes through the tentaces Oi course the
contact OF the water produces a kind OF respiration
There is undoubtedly change OF substance con
stantly produced between the external water and
the internal h1id.
The eggs which are very numerous IN these
animals are hung In lunches As numerous As the
partitions. There are poyps IN which there are
twenty aud In some greater number oi ounches
OF eggs hung around the lower opening oil the
stomach or on the internal wall OF these partitions
When the eggs ripe they escape either through
the stomach and mouth or between the partitions
through the tentaclcs ia the course OF this sum
mer have witnessed repeatedly this operation Ia
one OF those polyps which are common On these
shores They may very often be iound on the
piles OF the whsrves all along the shores oi the AT
antic 10 some Of them have witnessed the pro-
cess from the earliest stage When the young AM
mails escape from the egg, they have the same
shape ss the old one, but with this difference that
they have only five or ten tentacles arranged IN
such a way making diagram on the board al
terward they have i've additional teutacles and ~
20 on increasing TIL these appcndages become a.
most innumerable. have found that these tenta'
cles are uniformly mutlpes vi hive
The mouth appears TO be circular ou. when care
fully examined Il is found to have al elongated ap.
pearauce. la fact the mouth IS rather oblong and
IN the young animal that form is quite apparent
You will perceive that IN the young animal one OF
the tentacles is Just parallel with the straight line
Of the mouth and the four others src arranged
10 two pairs iatcrally. This point Is important as
shall show that there we have the hrst Indication
Of bilsteral symmetry with the anter rregion well
defined.
No nerves have been observed IA these snimsls
Nevertheless, we cannot doubt tina, they feel
Light acts upon them. They contract under strong
light They also contract under the influence oi
darkuess Ia mild light they expsnd completely
Some, indeed, can expand 10 the strongest light