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ftory which I have been able to confult, incline me to believe it to be a non-defcript. As the peculiarities of its ftructure may add to the knowledge of the natural hiftory of other animals of this genus, at present fo little understood, I have drawn out a more particular account of it; which, if you think it deferves attention, you may prefent to the Royal Society.

"This animal was found on the fouth-east coast of Barbadoes, clofe to Charles Fort, about a mile from Bridge Town, in fome fhoal water, feparated from the fea by the ftones and fand thrown up by the dreadful hurricane, which happened in the year 1780, and did fo much mischief to the ifland.

The wind, in the beginning of the ftorm, which was in the afternoon, blew very furiously from the north-west, making a prodigious fwell in the fea; and in the middle of the night changing fuddenly to the fouth-eaft, it blew from that quarter upon the fea, already agitated, forcing it upon the fhore with fo much violence, that it threw down the rampart of Fort Charles, which was opposed to it, although thirty feet broad, by the bursting of one fea. It forced up, at the fame time, immenfe quantities of large coral rocks from the bottom of the bay, making a reef along this part of the coaft for the extent of feveral miles, at only a few yards diftance from the shore.

"The foundings of the harbour were found afterwards to be intirely changed, by the quantity of materials removed from the bottom in different places. In the reef of coral was found an infinite number of large pieces of brain ftone, containing the hell of this animal; but the animals had either been

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long dead, or more probably deftroyed by the motion of the rocks in the ftorm: fome few of the brain-ftones, however, that had been thrown beyond the reef, and lodged in the thoal water, receiving less injury, the animals were preserved unhurt.

"The animal, with the shell, is almoft intirely inclofed in the brainftone, so that at the depth in which they generally lie, they are hardly difcernible through the water from the common furface of the brainftone; but when in fearch of food, they throw up two cones, with membranes twisted round them in a fpiral manner, which have a loose fringed edge, looking at the bottom of the fea like two flowers; and in this state they were discovered.

"The fpecies of Actinia, called in Barbadoes the animal flower, and common to many parts of that itland, although rarely before seen on this part of the coaft, was now found in confiderable numbers in this thoal water.

"The animal was firft obferved by captain Hendie, the officer commanding Fort Charles, in looking for fhells which were thrown up in great numbers from the bottom of the harbour. He found a piece of brain-ftone containing three of them in different parts of it. Some little time after, I was lucky enough to find another brain-ftone with two in it; one of them is the fpecimen in your poffeffion; the other was deftined for examination, of which the following is the account.

"The animal, when taken out of the fhell, including the two cones and their membranes, is five inches in length; of which the body is three inches and three-quarters, and the apparatus for catching its prey,

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ment; but the upper and lower ends are lying loofe.

"From the end of the body, between the two upper ends of thefe cartilages, arife what I fuppofe to be the tentacula, confitting of two cones, each having a fpiral membrane twining round it: they are clofe to each other at their bafes, and diverge as they rife up, being about an inch and a quarter in length, and nearly one-fixth of an inch in thickness at their base, and gradually diminishing till they terminate in points. The membranes which twine round these cones alfo take their origin from the body of the animal, and make five fpiral turns and a half round each, being loft in the points of the cones; they are loofe from the cone at the lowest fpiral turn which they make, and are nearly half an inch in breadth; they are exceedingly delicate, and have at fmall distances fibres running across them from their attachment at the stem to the loofe edge, which gives them a ribbed appearance. Thefe fibres are continued about one-tenth of an inch beyond the membrane, having their edges finely ferrated, like the tentacula of the Actinia found in Barbadoes: thefe tentacula fhorten as the fpiral turns become smaller, and are entirely lott in that part of the membrane which terminates in the point of the cone.

"The two cartilaginous fubftances by which the animal adheres to its fhell, are placed one on each fide of the body, and are joined together upon the back of the animal at their pofterior edges: they are about three quarters of an inch long, are very narrow at their anterior end, becoming broader as they go backwards; and at their pofferior end they are the whole breadth of the body of the animal. Upon their external furface there are fix tranfverfe ridges, or narrow folds; and along their external edges, at the end or termina

tion of each ridge, is a little emi-Behind the origin of these
cones arifes a fmall fhell, which,
for one fixth of an inch from its
attachment to the animal, is very
flender: it is about three-quarters
of an inch in length, becoming
confiderably broader at the other
end, which is flat, and about one-
third of an inch broad; the flat-
tened extremity is covered with a
kind of hair, and has riting out of

nence refembling the point of a
hair pencil, fo that on each fide of
the animal there are fix of thefe
little projecting ftuds, for the pur-
pofe of adhering to the fides of the
Thell in which the animal is inclof-
ed. The internal furfaces of thefe
cartilages are firmly attached to the
body of the animal, in their mid-
dle part, by a kind of band or liga

prey, which may be confidered as
its tentacula, about an inch and a
quarter.

"The body of the animal is at
tached to its fhell, for about three.
quarters of an inch in length, at
the anterior part where the two
cones arife, by means of two car-
tilaginous fubftances, with one fide
adapted to the body of the animal,
the other to the internal furface of
the fhell: the rest of the body is
unattached, of a darkish white co-
lour, about half an inch broad, a
little flattened, and rather narrow-
er towards the tail. The mufcular
fibres upon its back are tranfverfe;
thofe on the belly longitudinal,
making a band the whole length of
the body, on the edge of which the
tranfverfe fibres running across the
back terminate.

it two fmall claws, about one-fixth of an inch in length. If the hair, and mucus entangled in it, be taken away, this extremity of the fhell becomes concave, is of a pink colour, and the two claws riling out from its middle part have each three fhort branches, not unlike the horns of a deer. The body of this fhell has a foft cartilaginous covering, with an irregular but polifhed furface on this the cones reft in their collapsed flate, in which ftate the whole of the shell is drawn into the cavity of the brain-ftone, excepting the flattened end with the two claws.

"Before the cones there is a thin membrane, which appears to be of the fame length with the fhell juft defcribed. In the collapsed state it lies between the cones and the fhell in which the animal is inclofed; but when the tentacula are thrown out, it is alfo protruded.

The hell of this animal is a tube, which is very thin, and adapt ed to its body: the internal furface is fmooth, and of a pinkish white colour: its outer furface is covered by the brain-ftone in which it is inclosed, and the turnings and wind ings which it makes are very nume rous. The end of the fhell, which opens externally, rifes above the furface of the flone on one fide half an inch in height, for about half the circumference of the aperture, bending a little forwards over it, and becoming narrower and narrower as it goes up, terminating at laft in a point just over the centre of the opening of the hell on the other fide it forms a round margin to the furface of the brain-ftone. This part of the fhell is much thick er and ftronger than that part which is inclofed in the brain-ftone: its outer furface is of a darkish brown colour; its inner of a pinkish white.

"The animal, when at reft, is wholly concealed in its fhell; but when it feeks for food, the move. able thell is puthed flowly out with the cones and their membranes in a collapfed ftate; and when the whole is expofed, the moveable fhell falls a little back, and the membrane round each of the cones is expanded, the tentacula at the bafes of the cones having just room enough to move without touching one another. The thin membrane which lays between the cones and the inclofing fhell is protruded in the form of a fold, and lies over the external fhell which projects from the brain-ftone.

"The membranes have a flow fpiral motion, which continues dur ing the whole time of their being expanded; and the tentacula upon their edges are in conftant action. The motion of the membrane of the one cone feems to be a little different from that of the other, and they change from the one kind of motion to the other alternately, a variation in the colour of the mem brane at the fame time taking place, either becoming a fhade lighter or darker; and this change in the colour, while the whole is in motion, produces a pleafing effect, and is moft ftriking when the fun is very bright. The membranes, however, at fome particular times appear to be of the fame colour.

"While the membranes are in motion, a little mucus is often fe parated from the tentacula at the point of the cone. Upon the leaft motion being given to the water, the cones are immediately and very fuddenly drawn in.

"This apparatus for catching food is the most delicate and complicated that I have feen; but I fhall not trouble you with any conjec tures upon what that food may be, as

about two yards from the bottom of the well, and being furrounded with well rammed clay, the new water afcended in a small stream through the wooden pipe.

rofe about a foot above the top of the well in the leaden pipe; and, on bending the mouth of this pipe to the level of the furface of the ground, about two hogfheads of water flowed from it in twenty-four hours, which had fimilar proper ties with the water of St. A'kmund's well, as on comparifon both thefe waters curdled a folution of foap in fpirit of wine, and abounded with calcareous earth, which was copiously precipitated by a folution of fixed alkali; but the new water was found to poffefs a greater abun dance of it, together with numerous fmall bubbles of aerial acid or calcareous gas.

"Our next operation was to build a wall of clay against the moraffy fides of the well, with a wall of well-bricks internally, up to the top of it. This completely stopped out every drop of the old water; and, on taking out the plug which had been put in the wooden pipe, the new water in two or three days rofe up to the top, and flowed over the edges of the well.

"Afterwards, to gratify my cu riofity in feeing how high the new fpring would rife, and for the agree able purpose of procuring the water at all times quite cold and fresh, I directed a pipe of lead, about eight yards long, and three-quarters of an inch diameter, to be introduced through the wooden pipe defcribed above, into the ftratum of marl at the bottom of the well, fo as to stand about three feet above the furface of the ground. Near the bottom of this leaden pipe was fewed, between two leaden rings or flanches, an inverted cone of stiff leather, into which fome wool was stuffed to stretch it out, so that, after having paffed through the wooden pipe, it might completely fill up the perforation of the clay. Another leaden ring or flanch was foldered round the leaden pipe, about two yards below the furface of the ground, which, with fome doubles of flannel placed under it, was nailed on the top of the wooden pipe, by which means the water was perfectly precluded from rifing between the wooden and the leaden pipes.

"The new water has now flowed about twelve months, and, as far as I can judge, is already in creafed to almost double the quan tity in a given time; and from the rude experiments I made, I think it is now lefs replete with calcareous earth, approaching gradually to an exact correfpondence with St. Alkmund's well, as it probably has its origin between the fame itrata of earth.

"As many mountains bear incontestable marks of their having been forcibly raised up by fome power beneath them; and other mountains, and even islands, have been lifted up by fubterraneous fires in our own times, we may fafely reafon on the fame fuppofition in refpect to all other great elevations of ground. Proofs of these circumftances are to be seen on both fides of this part of the country. Whoever will infpect, with the eye of a philofopher, the lime-mountain at Breedon, on the edge of Leicestershire, will not hefitate a moment in pronouncing, that it has been forcibly elevated by fome power beneath it; for it is

"This being accomplished, the bottom of the well remained quite

dry, and the new water quickly of a conical form, with the apex

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veral others which were nearer the place where the pin was put in.

the impreffion on the leaf was made in fuch a way as to affect the petiolus, the motion took place. When, therefore, I wanted to confine the motion to a fingle leaf, I either touched it fo as only to affect its own petiolus, or, without meddling with the leaf, touched the petiolus with any small-pointed body, as a pin or knife.

By compreffing the univerfal petiolus near the place where a partial one comes out, the leaf moves in a few feconds, in the fame manner as if you had touched the partial petiolus.

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"Whether the impreffion be made by puncture, percuffion, or compreffion, the motion does not instantly follow generally feveral feconds intervene, and then it is not by a jirk, but regular and gradual. Afterwards, when the leaves return to their former fituation, which is commonly in a quarter of an hour or lefs, it is in fo flow a manner as to be almost impercep

tible.

"On sticking a pin into the univerfal petiolus at its origin, the leaf next it, which is always on the outer fide, moves first; then the fift leaf on the opposite fide, next the fecond leaf on the outer, and fo on. But this regular progreffion feldom continues through out; for the leaves on the outer fide of the pinna feem to be affected both more quickly, and with more energy, than thofe of the inner, fo that the fourth leaf on the outer fide frequently moves as foon as the third on the inner; and fometimes a leaf, efpecially on the inner fide, does not move at all, whit thofe above and below it are affected in their proper time. Sometimes the leaves at the extremity of the etiolus move fooner than fe

"On making a compreffion with a pair of pincers on the univerfal petiolus, between any two pair of leaves, thofe above the compreffed part, or nearer the extremity of the petiolus, move fooner than thofe under it, or nearer the origin; and frequently the motion will extend upwards to the extreme leaf, whilft below it perhaps does not go farther than the nearest pair.

If the leaves happen to be blown by the wind against one another, or against the branches, they are frequently put in motion; but when a branch is moved gently, either by the hand or the wind, without ftriking against any thing, no motion of the leaves takes place.

"When left to themfelves in the day-time, fhaded from the fun, wind, rain, or any disturbing caufe, the appearance of the leaves is dif ferent from that of other pinnated plants. In the laft a great uniformity fubfifts in the refpective polition of the leaves on the pinna; but here fome will be seen on the horizontal plane, fome raised above it, and others fallen under it; and in an hour or fo, without any order or regularity, which I could obferve, all thefe will have changed their refpective positions. I have feen a leaf, which was high up, fall down; this it did as quickly as if a strong impreffion had been made on it, but there was no cause to be perceived.

"Cutting the bark of the branch down to the wood, and even feparating it about the fpace of half an inch all round, fo as to stop all communication by the veffels of the bark, does not for the first day affect the leaves, either in their pofition or their aptitude for motion.

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