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work of threads that carried them. They have become
immediately paralyzed by the division of the threads, but
those that remain on the tube are unaffected by the vio-
lence. Subjecting one of the animals so cut out to the
action of the compressorium, with a power of 560 diame-
ters, the arms are seen to be formed of globose cells, made
slightly polyhedral by mutual pressure, set in single series.
The interior of these organs is divided by partitions, placed
at intervals of about the diameter. Some at least of the
cells contain a small bright eccentric nucleus.

When the tissues were quite crushed down by the press-
ure of the compressorium, a quivering motion was visible
among the disjointed granules, but it was very slight. No
trace of cilia, nor any appearance of ciliary motion, was
perceptible during life.

When I first discovered these strange beings, I was as
much astonished by what I saw as you are; nor could 1
imagine to what class of animals they were to be referred.
Neither did I know whether their presence on the tube of
the worm was a mere accident, or whether it indicated a



392 EVENINGS AT THE MICROSCOPE

predominal instinct. On both these points, however, light
has been shed.

This larger Sabella tube was not the only one infested
with the parasites. I observed them on at least two smaller
specimens of the same species, in the same situation, and
with precisely the same movements. Th& extremity of
one of these smaller tubes I cut wholly off, and placed
in the live-box of the microscope. Two of the parasites
only were on it, which were active at first, but in about
an hour probably from the exhaustion of the oxygen in
the small quantity of water enclosed they decomposed,
or rather disintegrated, the outline dissolving, and the
external cells becoming loose and ragged, and the whole
animal losing its definite form.

One of these specimens, however, while yet alive and
active, afforded me an observation of value. I had already
associated the form conjecturally with the Hydroid Poly-
pes, and was inclined to place it in the family Corynidce^
considering the arms to be tentacles, and the head-lobe
to be homologous with them in character, but abnormal
in form. It appeared to be a three-tentacled Coryne, with
the tentacles simple instead of capitate. But while I was
observing the individual in question, I saw it suddenly
open the head-lobe, and unfold it into the form of a broad
shovel-shaped expanded disk, not however flat, but with
the two halves inclining toward each other, like two leaves
of a half -opened book. This immediately reminded me of
the great sucking-disk which, as I lately told you, I had
seen evolved from the obtuse summit of Stauridia producta,
and confirmed my suggestion of the natural affinities of
the form.

Altogether unlike, in their shape, and in the unwonted



ZOOPHYTES 393-

vivacity and peculiarly human character of their move-
ments, all the other members of their natural family that
I had ever seen or heard of, these curious creatures have
afforded much entertainment, not only to myself, but to
those scientific friends to whom I have had opportunities
of exhibiting them. When I see them surrounding the
mansion of the Sabella, gazing, as it were, after him as he
retreats into his castle, flinging their wild arms over its
entrance, and keeping watch with untiring vigilance until
he reappears, it seems to require no very vivid fancy to
imagine them so many guardian demons; and the Lares
of the old Koman mythology occurring to memory, I de-
scribed the form under the scientific appellation of Lar
Sabellarum. You may, however, if it pleases you better,
call them "witches dancing round the charmed pot."

The Polypes that we have as yet been looking at are
all of simple structure individually, though some of them
we have seen united into a very populous community of
compound life. We will now look at some whose organ-
ization is of a higher, that is more complex, character.

On this old worm-eaten oyster shell which has been
dredged up from the bottom of the sea you observe sev-
eral rounded lumps. They are of a cream-white hue, of
somewhat solid texture, tough and hard to the touch, and
studded all over with shallow depressions or pittings. The
largest of these is not more than an inch and a half in
height, by two-thirds of an inch in thickness; but speci-
mens often occur of twice or thrice these dimensions, and
much more divided than this; sometimes forming a rude
resemblance to a hand of stumpy round fingers of sodden
flesh whence the fishermen call the object, "Dead men's
fingers," or, sometimes, by a comparison equally apt,



394 EVENINGS AT THE MICROSCOPE

"Cows' paps." To zoologists it is known as Alcyonium
digitatum.

Certainly there is nothing very attractive in these white
lumps, as they now appear; but then they are now in un-
dress; they do not expect to see company out of water.
Their drawing-room is beneath the waves, in some sub-
merged cave of ocean, where the sun's ray never pene-
trated, and where the only light is that dim green haze
reflected from the sand and shingle of the sea-floor, save
when, on gala occasions perchance, the Laomedece that
fringe the walls light up their myriads of fairy lamps,
and the tiny Medusae, crowd in to the watery festivities
with their elfish circlets and spangles of living flame. It
is then that the Cows '-paps "take their hair out of paper,"
and display their loveliness to advantage.

Unfortunately, we have no card of invitation to these
submarine routs, but perhaps we may induce one of the
more juvenile of these beauties to indulge us, as a special
favor, with a sample of the effect; particularly if we can
improvise a ball-room suited to the occasion. Let us
try.

Selecting the very smallest specimen a tiny thing no
)arger than a pea I try to detach it without injury, by
inserting the tip of my pocket-knife under the frilled
lamina of oyster-shell on which it rests, and working off
the fragment. I have succeeded: here it is; its attach-
ment unbroken; it is still firmly adherent to the severed
slice of shell, which is so small that I can drop it with its
burden into this narrow trough of glass. The whole con-
cern trough, shell, and polype is now to be dropped
into this capacious jar of freshly dipped sea-water, and
put away for an hour into a dark closet.



ZOOPHYTES

Now let vis ess the result. Yes, it is as I expected.
The united stimulus of the darkness and the sea-water has
acted on the Cow's-pap, just as would the rising and cov-
ering tide in its native cavern, after it had been left ex-
posed for some hours by the recess of the sea. It is fully
expanded, and is now as lovely as just now it was un-
pleasing.

In the first place it is swollen to twice its former di-
mensions, and has acquired at the same time a semi-pel-
lucidity, and a more delicate hue. But in place of the
pits on the surface (there were not more than half a dozen
in this little specimen, which makes it more suitable for
examination), it is covered with tall polypes, standing out
on all sides, of crystalline clearness and starry forms, each
eminently beautiful in itself, and surrounding the whole
mass with a sort of atmosphere of almost invisible and im-
palpable lustre peculiarly charming.

Coy as these deep-water strangers are of displaying
their beauties in our glaring aquariums, they will bear,
when once they are expanded, a good deal of shaking with
equanimity. Hence I may be able to transfer the trough
with its contents from the jar to the stage of the micro-
scope, and thus enable you to gaze on its details for a lit-
tle while, before the dull sensorium of the creature is suffi-
ciently warned of its ungenial position to cause it to shut
itself up and resume its ugliness.

As the protruded polypes are exactly alike, it will be
enough to confine our attention to one. It is an elevated
tubular column of translucent substance, terminating in an
expanded flower of eight slender pointed petals, which
spring outward with a graceful swell, so as to give the
form of a shallow bell to the general outline. The base



39(3



EVE XING S AT THE MICROSCOPE



springs, like the foot of a tree, from the margin of a cell,
which penetrates the substance of the mass, into which we
can see far down, and into which the whole of the now
extended and expanded blossom was withdrawn when we
first saw it, leaving only the shallow depression to mark
its situation.

The form of the column is in general that of the trunk
of a tree, or that of a long cone; but there is a sudden
constriction just above the base, and another below the




POLYPES OF COW S-PAP.



point, where what may be called the flower expands. It
is the petals of this latter which constitute the principal
charm of this creature. They are, properly speaking, the
tentacles of the Polype, answering in function and position
to those on the Laomedea, but differing considerably from
them in form. Each of the eight is thick and broad at
its origin, and quickly tapers to a point: on each of two
opposite sides viz., those which look toward the two ad-
joining tentacles runs a row of delicately slender fila-
ments, which at the middle part of the tentacle are moder-



ZOOPHYTES 397

ately long, but diminish regularly as they approach either
end. Starting from the side of the tentacle, in the plane
of its transverse diameter, these elegant pinnae presently
arch downward, but with perfect uniformity and symme-
try. By means of the high magnifying power which I
have now applied, each of these pinnaa is seen to be rough-
ened with whorls of knobs, which are accumulations of
cnidae, analogous to those which we lately demonstrated
in the tentacle of Laomedea.

In the midst of the area surrounded by the petal-like
tentacles, a narrow slit opens into the stomach. This or-
gan is a flat sac, resembling an empty pillow-case hanging
down in the centre of the column, and open at the lower
end. From this end, which does not extend to more than
one -sixth of the depth of the cavity, three threads, much
convoluted and irregularly thickened, spring off at each
side and arch downward, for a short distance. These are
the reproductive organs, which fringe the free edges of as
many delicate membranes which run up as perpendicular
partitions between the stomach and outer wall, uniting
with both, and thus dividing the space surrounding the
stomach into chambers open at the bottom. There are
eight of these septa, but one on each side is destitute of
the fringing convoluted thread.

The whole surface of the interior the walls, the stom-
ach, and the septa is clothed with fine vibratile cilia, by
the action of which constant currents are maintained in
the water, which bathes every part of the cavity, freely
entering at the mouth. We can distinctly trace these cil-
iary currents hurling along with irregular energy the prod-
ucts of digestion, in the form of translucent granules,
especially along the edges of the septa.



398 EVENINGS AT THE MICROSCOPE

Though the substance of the polype be soft and flexi-
ble, it contains solid elements. Just below the expansion
of the tentacular blossom we see imbedded in the skin a
vast aggregation of calcareous spicula. Individually, these
are very minute, and their form is swollen in the middle,
and taper at each extremity, the whole roughened with
projecting knots. Collectively, they are grouped in regu-
lar forms, crowded into dense masses at the foot of each
tentacle; the mass having a three-pointed outline, of which
the central and largest point runs up into the tentacle.

Toward the lower region of the column, spicula again
occur, scattered throughout the skin, and crowded into
groups, one on each interseptal space. These spicula are
of a very different shape from the upper ones; for they
form short thick cylinders, with each end dilated into a
star of five or six short branches, which are again starred
at their truncate ends.

If we now sacrifice our little Cow's-pap to our scien-
tific curiosity we shall see something of its internal struct-
ure. When removed from the water, the blower-like poly-
pes soon retract. I now cut open the mass lengthwise with
a keen knife, and you see that it is permeated by canals
running from the base toward every part of the circum-
ference, dilating here and there to form the cells which
protrude and retract the polypes. This is a complete sys-
tem of water-supply: the surrounding sea- water, entering
at the mouths of the several polypes, bathes the whole
interior, and conveys oxygen and the products of diges-
tion together to every part of the compound organism.

The fleshy substance which surrounds these canals is
of a loose spongy character, and grates beneath the knife;
a circumstance which is owing to the predominance of the



ZOOPHYTES

calcareous element here, as you will see when I extract a
small portion of it, and, laying it on a slip of glass, treat
it with caustic potash. The microscope now reveals a large
number of spicula, far larger than those we have hitherto




SPiCULA OP COW'S-PAP.



observed, and different from either sort in form. These
resemble very gnarled branches of oak, with the branch-
lets broken off close to their origin, leaving ragged and
starred ends.



400 EVENINGS AT THE MICROSCOPE



CHAPTER XIX

SEA-ANEMONES: THEIR WEAPONS

A VERY vast amount of the energy of animal life is
spent either in making war, or in resisting or evad-
ing it. Offence and defence are sciences which the
inferior creatures can in nowise neglect, since all are inter-
ested in one or other, and many in both; and various are
the arts and devices, the tricks and stratagems, the in-
stincts and faculties, employed in that earnest strife which
never knows a suspension of hostilities. All classes of
animals, invertebrate as well as vertebrate, are warriors
by profession: the Spider is as carnivorous as the Lion,
and more strategic; and the invisible Brachion is as ruth-
less and insatiable as either.

An enumeration and description of the diverse weapons,
by means of which this truceless warfare is carried on,
would make a volume : nor would the subject be then ex-
hausted; for since it enters so largely into the very exist-
ence of animal life, the discoveries of advancing science
are ever bringing to light new forms and modifications,
strange and unexpected contrivances, all calculated to en-
hance our view of the inexhaustible resources of the Lord
God Omnipotent, "who is wonderful in counsel, and excel-
lent in working."

I am going to bring under your notice this evening
some highly curious examples of animal weapons, of which
the very existence was until lately altogether unsuspected;
yet so profusely distributed that they are eminently char-



SEA-ANEMONES: THEIR WEAPONS 401

aeteristic of the two great classes of animals we have been
recently considering; viz., the Medusae and the Zoophytes.
They have repeatedly fallen under our observation in ex-
amining the specimens of these creatures which we had
selected, but I had reserved the fuller elucidation of them
for an occasion in which they should come before us under
circumstances of such unusual development as greatly to
facilitate our researches. The weapons I speak of are the
cnidce or nettling-cells.

Look at this beautiful Scarlet-fringed Anemone (Sagarta
miniata), expanding to the utmost its disk and tentacles in
the clear water of the tank. I touch its body; instantly
the blossom-like display is withdrawn; the column closing
over it in the form of a hemispherical button, which goes
on contracting spasmodically. At the same time see these
white threads which shoot out from various points of the
surface; new ones appearing at every fresh contraction,
and streaming out to a length of several inches resem-
bling in appearance fine sewing cotton, twisted and tangled
irregularly.

Now the animal has attained its utmost contraction,
and the threads lengthen no more. But already they are
disappearing; each is returning into the body by the ori-
fice at which it issued. It is, as you may see by examin-
ing it carefully with a lens, gradually contracting into
small irregular coils, at that end which is attached to the
animal; and these little coils are, one* after another, sucked
in, as it were, through an imperceptible orifice.

Before the whole have disappeared, we will secure a
portion for examination. For this end I cut off with a
sharp scissors about one-sixth of an inch of the extremity
of one of the threads, which now I transfer to a drop of



402



EVENINGS AT THE MICROSCOPE



sea- water in the compressorium. These threads are called
acontia.

Examining this fragment under a low power of the mi-
croscope, we readily see that, though at first it seems a
solid cylinder, it is really a flat narrow ribbon with the
edges curved in, which can at pleasure be brought into
contact, and thus constitute a tube. Like all other in-
ternal organs in these animals, its surface is richly ciliated,
and the ciliary currents not only hurl along whatever float-




PORTION OP ACONTIUM (flattened).

ing atoms chance to approach the surface, but cause the
detached fragments themselves to wheel round and round,
and to swim away through the water. Though there is
not the slightest trace of fibre in the structure of the
acontium, when scrutinized even with a power of eight
hundred diameters, the clear jelly, or sarcode, of which its
basis is composed, is endowed with a very evident con-
tractility; the filament can contract or elongate; can ex-
tend itself in a straight line, or throw its length into spiral
curves and contorted coils; can bring its margins together,



SEA-ANEMONES: THEIR WEAPONS 403

or separate them in various degrees; can perform the one
operation in one part, and the other at another, and thus
can enlarge or attenuate the general diameter of the cord,
apparently at will; and some of these changes can be
effected even in the fragment detached from the animal,
thus proving that the motile power, whatever it is, is
localized in the constituent tissue itself.

Under pressure the edges of the flattened acontium ap-
pear to be thronged with clear viscous globules, overlap-
ping one another, and protruding; indicating one or more
layers of superficial cells, doubtless forming the epithe-
lium. As the pressure is increased, these ooze out as
long pear-shaped drops, and immediately assume a per-
fectly globular form, with a high refractive power. Below
these are packed a dense crowd of cnidce, arranged trans-
versely.

Before we proceed to the examination of these curious
organs in detail, it may be well to devote a moment's at-
tention to the mechanism by which the acontia themselves
are projected from the body. As this was first described
(so far as I am aware) by myself, 1 I will take the liberty
of citing some of my observations on the matter.

"The emission of the acontia is provided for by the
existence of special orifices, which I term Cinclides. The
integument of the body, in the Sagartice, is perforated by
minute foramina, having a resemblance in appearance to the
spiracula of Insects. They occur in the interseptal spaces;
opening a communication between these (and therefore the
general visceral cavity) and the external water. It follows
that they are placed in perpendicular rows, but I have not

1 In a memoir entitled "Researches on the Poison Apparatus in the
Actiniadse " read before the Royal Society, Feb. 4, 1858.



404



EVENINGS AT THE MICROSCOPE



been able to trace any other regularity in their arrangement.
So far as I have seen, they are so scattered that one, two, or
even more contiguous intersepts may be quite destitute of a
cinclis. I would not, however, attach too much weight to
this negative evidence, since the animal has the power of
closing them individually at will, and
that so completely that the most careful
scrutiny does not detect their presence.

"Perhaps the best mode of exam-
ining them is to put a small specimen
of S. diantlius or S. bellis into a narrow
parallel-sided glass cell, filled with sea-
water. After a while the animal will
be much distended; the exhaustion of
the oxygen impelling the Anemone to
bathe its organs with as large a quan-
tity of the fluid as it can inhale. The
pellucidity of all the integuments will
be thus greatly increased. A strong

lamplight being now reflected, by means of the mirror,
through the animal on the stage of the microscope, an
inch or a half-inch object-glass will probably reveal the
orifices in question with much distinctness.

"The appearance of the cinclides may be compared to
that which would be presented by the lids of the human
eye, supposing these to be reversed; the convexity being
inward. Each is an oval depression, with a transverse
slit across the middle. When closed, this slit may some-
times be discerned merely as a dark line the optical ex-
pression of the contact of the two edges; but, when slightly
opened, a brilliant line of light allows the passage of the
rays from the lamp to the beholder. From this condition




SEA-ANEMONES: THEIR WEAPONS 405

the lids may separate in various degrees, until they are
retracted to the margin of the oval pit, and the whole
orifice is open.

"The dimensions of the cinclides vary not only with the
species, and probably also with the size of the individual,
but with the state of the muscular contraction of the in-
tegument, as, also, I think, with the pleasure of the ani-
mal. In a small specimen of S. dianihus, I found the
width of a cinclis, measured transversely, itath of an inch;
but that of another, in the same animal, was more than
twice as great; viz., mth of an inch. This was on the
thickened marginal ring, or parapet, which in this species
surrounds the tentacles, where the cinclides are larger than
elsewhere. Watching a specimen of S. nivea under the
microscope, I saw a cinclis begin to open, and gradually
expand till it was almost circular in outline, and ^hrth of
an inch in diameter. I slightly touched the animal, and
it in an instant enlarged the aperture to irtath of an inch.
In a specimen of S. bellis, less than half-grown, I found
the cinclides numerous, and sufficiently easy of detection,
but rather less defined than in dianthus or nivea. They
occurred at about every fourth intersept, three intersepts
being blind for each perforate one, and about three or four
in linear series, but not quite regularly in either of these
respects. In this case they were about sVth of an inch in
transverse diameter a large size; and I measured one
which was even i&th of an inch. By bringing the animal
before the window, I could discern the light through the
tiny orifices with my naked eye.

"From several good observations, and especially from
one on a cinclis, widely opened, that happened to be close
to the edge of the parapet of a dianthus^ I perceived that



406 EVENINGS AT THE MICROSCOPE

the passage is not absolutely open, at least in ordinary, but
that an excessively thin film lies across it. By delicate
focusing I have detected repeatedly, in different degrees
of expansion, and even at the widest, the granulations of
a membrane of excessive tenuity, and one or two scattered
cnidce, across the bright interval. On another occasion, in
the case of a cinclis at the edge of the* parapet, a position
singularly favorable for observation, I saw that this subtle
film was gradually pushed out until it assumed the form
of a hemispherical bladder, in which state it remained as
long as I looked at it. At the same time the outline of
the cinclis itself was sharp and clear, when brought into
focus further in. The film, whatever it be, is superficial,
and does not appear to be a portion of the integument
proper. I take it to be a film of mucus (composed of de-
organized epithelial cells), which is constantly in process
of being sloughed from all the superficial tissues in this
tribe of animals, and which continues tenaciously to invest
their bodies, until, corrugated by the successive contrac-
tions of the animal, it is washed away by the motions of
the waves. As, however, one film is no sooner removed
than another commences to form, one would always expect
external pores so minute as these to be veiled by a mucus-
film in seasons of rest.

"The pressure of this film is sufficient evidence that the
cinclides are not excretory orifices for the outflow of the
respired water, in the manner of the discharging siphon
in the Bivalve MOLLUSCA at least that no current con-



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