The Aquarium (Gosse)/Chapter 6
CHAPTER VI.
What more felicity can fall to creature
Than to enjoy delight with liberty?
Spenser.
A WALK THROUGH PORTLAND.
Some jottings of the amœnities of Portland, which I hastily put down in the course of a pedestrian excursion through it, may not be unacceptable to such of my readers as have not had an opportunity of becoming acquainted with it; for it is rather an original little isle, and has some claims of its own to attention.
After clearing that city of stone blocks which I have before mentioned, I wound round the foot of the hill, and mounted the steep village of Fortune's Well, with its pretty houses and nice shops, all of stone of course (on the principle of patronizing the home manufacture) and the substantial church, and neat rectory, where dwells,—a blessing to the inhabitants,—my venerated friend, the Rev. Mr. Jenour. As I toiled up the precipitous road in the summer's sun, it was a relief to turn, at times, and solace my eyes with the almost boundless prospect that expanded behind,—every where indeed, except just in front. The villages of Fortune's Well and Chesil, united into one, lie just beneath; the stretches away in a line, of which the eye fails to detect the termination, the Chesil Beach dividing two waters, both beautiful; the one undulating with the long swells of the Atlantic, the other smooth, or at most but rippled. Wyke crowns the hill just opposite with its tall tower and the hedge-rowed fields chequering the slopes around, and beyond it sweeps a long blue line of coast with dim headlands here and there, as far as Torquay.
I passed the Quarries rapidly, for I wished to get to the southern end of the island by low-water, desiring, as the time was favourable, to explore the rocky caves and coves that indent the precipitous coast;—and posted on through two other villages, Highstone, and Wakeham, which, like the former two, merge into one. I met here with a garrulous old man, a characteristic specimen of the island population. Like nine-tenths of his fellows he had united the trades of smuggler and stone-cutter; gave me some graphic anecdotes of the adventures of his younger days, when "running tubs," and described the sad fate of his hopeful son, a stone-hewer like himself, who was suddenly snatched from his side by a block of stone falling upon him, from the seaward cliff where they were quarrying. "The stone split my poor boy right open," said the old man, and pathetically added, "I've never worked a stroke since!"
Few specimens of vegetation can Portland produce that attain the dimensions of a tree; but near the middle there is a pretty grove of horse-chestnut, maple, elm and other trees, of no great altitude certainly, but imparting a rural aspect to the vicinity of Pensylvania Castle, the quondam seat of the governor of the island. Beside this a narrow road scarped out of the rock brings the traveller to a far more ancient structure, which tradition assigns to
"—That red king who, while of old
Through Bolderwood the chase he led,
By his loved huntsman's arrow bled."
It is named indifferently Rufus Castle or Bow-and-arrow Castle, from the square loop-holes with which its solid walls are pierced. A single square tower remains, on the summit of an almost isolated mass of rock scarcely more than commensurate with itself, along which the road winds forty feet deep, through the arch of a bridge, which leads to the castle-door from the adjacent heights.
A most magnificent prospect expands as we pass under this bridge. We are on the verge of a precipice, with a little Cove below, called Church Hope, the only landing for a boat along this coast. Broken masses of stone are heaped in the wildest confusion on every side, and all up the craggy slopes, a wilderness of grey stone, of which the aspect is painfully desolate, and, so to speak, ruined. A steep and difficult road has been cut down to the beach, and about half-down is a hollow, whither the inhabitants resort for water. Beneath a stone a stop-cock is inserted, that none may be wasted of a fluid so precious: a woman with her pails coming down informed me that every drop they drink has to be fetched in this laborious manner, and carried up the steep precipice. To make it worse, the spring fails in droughts, when they must resort still lower, to a little stream that breaks out of the Cliff below.
A little way beyond Church Hope, going southward, there is a vast chasm, produced by some convulsion of nature prior to all tradition. Its general course is straight, and parallel with the coast; running perhaps a quarter of a mile in length, and thirty yards in average width (I speak conjecturally, for I had no means of measuring it); the stone sides rising perpendicularly, exactly like walls, with the stratification imitating courses of regular masonry, but of cyclopean dimensions. Long brambles, shooting from the fissures, spread in patches, which assist the glossy ivy to throw a graceful drapery over the walls of this yawning gulf; and the suspicious blackbird that shot out of her nest at my approach, and the lesser birds that hopped about, shewed that, however awful the scene appeared to me, it was not without its charms for these gentle denizens.
I was struck with the resemblance which this phenomenon bears to a chasm in Lundy, that I have elsewhere described. No doubt in each case the effect was produced by the partial separation and recession of a slice (if I may use so undignified a term) of the precipice, which, instead of proceeding to a fall, which would simply have opened a new line of the coast-edge, became, from some hindering cause, prematurely arrested midway, and has remained so fixed. This is not the only instance which I remarked of parallelism to Lundy in phenomena; though the geological formation of that rocky islet is very different, being granite.
At length I approached the southern extremity of the isle, passing through another village called Southwell, or, as it is pronouuced, "Suthill," and coming into sight of the two white light houses that are erected above the Bill. It is remarkable how generally the names of the hamlets contain the word "well," showing doubtless that the existence of a spring of water was the determining cause of the position of a village. Here I turned off to the left, deferring to another occasion a sight of the extreme point or Bill, for lack of time, as I was desirous of exploring another singular natural curiosity, Keeve's Hole. Over a breadth of ploughed land, sown with clover in strips, I made my way towards the edge of the cliff, but before reaching it came suddenly on an oval pit about eighteen yards long by eleven wide, and ten feet deep in the middle where the flat bed of stone is uncovered. The central part of this bed has dropped away, and though the aperture, the thickness of the stratum being about three feet, I looked down into an ample cavern. The interior was somewhat dark, but sufficient light was admitted to allow of the sides and bottom being obscurely discerned; a light which came not from the orifice in the roof through which I was peering, but from a gallery which, with some windings, opened on the face of the cliff, and through which the waves of the sea were dashing with a reverberating roar. I could scarcely look down into the abyss without a shuddering dread, which was not diminished by the story told me by a lad near, of a fool-hardy fellow who, to elicit the admiration of his comrades, must needs jump across the chasm. He failed to make good his footing, and fell through into the cavern, which, as well as I could judge, is about fifty feet deep. Strange to say, he was not killed, nor materially hurt; and his companions having procured ropes from the neighbouring Lighthouse got him out, frightened, and it may be charitably hoped, somewhat instructed by the adventure. Whether the name of Keefe's, Keeve's or Cave's Hole, as it it variously written, was derived from this involuntary explorer, I could not learn.
The sea-cliffs all about this part are highly picturesque and romantic. The strata of stone are quite horizontal, resembling courses of masonry, and the action of the waves and weather in the lapse of ages has worn away the softer portions, producing a succession of caverns, supported by uncouth pillars, with projecting groins and buttresses. Sometimes these caves run into the solid land; at others they open out again upon the sea at a little distance, making long corridors, or short series of arched vaults, and, occasionally, as in the example of Keeve's Hole just described, the yielding of the roof makes a skylight in the interior; so that the various effects of the light struggling with the gloom in these caves are the most picturesque imaginable.
The sense of grandeur too is greatly augmented by the perpetual moaning and roaring of the sea, which breaks upon the foot of the rocks, and as it rolls inward reverberates from the interior;—a sound indefinitely prolonged along the sinuous coast.
"κῦμα πολυφλοίσβοιο θαλάσσης,
Aίγιαλῷ μεγάλφῳ βρέμεται, σμαραγεῖ ὃέ τε πόντος."
A slender thread of water falling from the top of the cliff over the mouth of these cavities, greatly increased the romantic effect; after rainy weather, I can well suppose it a fine columnar cascade, though now it was small.
South of these arches, the cliffs become low and shelving, so that it was not difficult to scramble down to the water-side. The wash of the sea, however, was much too great to make it anything of a collecting ground. Besides the smooth Anemone, a few Trochi and Purpurœ, a Tansy or two (Blennius pholis), and other equally common things, no animal life was visible. Algæ were fine, of certain species. Laminaria digitata was waving in great magnificence; and that singular plant Himanthalia lorea, consisting of long and slender thongs springing from the centre of a flat button: Chondrus, Rhodymenia, Ceramium, and Polysiphonia, of common sorts, were all luxuriant in the sheltered nooks between the boulders. I got also some deep-red mossy tufts of the delicate Callithamnion byssoideum, growing on the stems of other Algæ; but on the whole my excursion was fruitless in respect to natural history, though prolific in entertainment.
THE TANSY.
One is apt to slight, as too mean to be worthy of notice, those objects which, are very common, though they may possess as many points of intrinsic interest as others, which, because they are more rare, occupy a more prominent place in our regard. I have two or three times passed by the Smooth Blenny, Shanny, or, as it is here called, Tansy (Blennius pholis), with somewhat of a contemptuous notice, which really it is not deserving of. For, though it is so abundant in every shallow pool that idle little boys, on Saturday half-holidays, make it the constant object of their sporting excursions, as their metropolitan cousins resort to the suburban canals to catch Tittle-bats,—the Tansy is worth putting into an Aquarium. Some specimens are ugly enough, it is true, both in form and colour; but others are quite attractive: they vary much from an uniform blackish olive, to a mixture of bright colours, as green, white and yellow; and the eyes are almost always beautifully brilliant, the large iris being of a vivid scarlet. It is an amusing fish in captivity, displaying a mixture of impudence and timidity, coming out fiercely to snatch a morsel of food from before a fellow fish's mouth, and then darting charily under the shadow of a rock to eat its treacherously gotten booty.
What makes this fish more than usually interesting, is, that it is one of those species which construct an elaborate nest for the deposition of their eggs and the hatching of their young:—
Ovid.
I have not had the good fortune to meet with the structure myself, and shall therefore refer my readers to the details mentioned by Mr, Couch in his "Illustrations of Instinct" (p. 252 et seq.), where the construction of the little dwelling of fragments of coralline and other sea-weeds, interwoven by silken threads, its suspension from an overhanging rock, the deposition therein of the amber-coloured eggs, the habits of the new-born young, the danger they incur from predatory enemies, and the vigilant care of the affectionate parent,—are well described.
THE PEACOCK'S TAIL.
One of the most interesting of our native sea-weeds is the Peacock's Tail (Padina pavonia). It is so called from its shape, which, springing from a point, expands into a broad fan, with an outline forming, in fine fronds, nearly three fourths of a circle. A more apt comparison would perhaps be the Turkey's tail, as its form is more closely like, and the concentric bands add to the resemblance. I had been familiar with the plant on the shores of Jamaica, for it is essentially a tropical species, but had never yet seen British specimens in their native haunts: it is marked as rare in our books, and is confined to a few localities on the Channel coast. My friend Mr. Thompson, however, taught me to look for it at Weymouth.
At the foot of the Nothe, bordering its southern side throughout its length, the shore at low-tide runs off in wide flat ledges, the structure of which I have already described. On these as one dips and another rises, a number of wide shallow pools lie in a sort of chain parallel to the low cliffs. Here I was instructed to watch for the first appearance of the pretty Peacock's Tail.
Unlike most of our Algæ, it is an annual plant, to be found only in the summer. The cold of autumn withers its fan-like fronds, and the waves soon wash away all trace of their existence, and it is not until somewhat late in the spring that we detect the germinating fans of our little friends again. Though I instituted careful examinations of the spots indicated at intervals of two or three days, it was almost the last of May before I could detect the minute thing springing from the mud in the tepid pool. Others however, soon appeared, and grew fast, so that by the middle of July numerous beds of them were to be found, in which the plants had attained almost their full dimensions, the fronds varying from one to two inches in diameter, Mr. Thompson has endeavoured to propagate this pretty Alga with entire success; collecting the fronds from their native site, when fully ripe, he scattered them in similar situations all along the shore; so that now, under Sandsfoot Castle, and on the ledges between this and Byng Cliff, and in a little bight of the rocks below the Nothe, there are what I may call flourishing gardens of the Padina, fully established, and needing no further care for their perpetuity.
It is a curious and interesting Alga, not only for its singular form, but because of its texture, which is delicately membranous, its colour, which is pale whitish olive or drab, marked with numerous concentric bands or zones, its surface, which is covered with a fine whitish deciduous powder, and its circular margin (often split), which is fringed with a line of very minute hairs, set at an angle from the plane of the frond. The sides of the frond frequently curve inward and form scrolls. The specimens will live a good while in the Aquarium: they are somewhat difficult to dislodge in a growing state, owing to the extreme tenuity and tenderness of their point of attachment, and to the softness of the rock, a sort of indurated clay, on which (at least with us) they generally grow; a substance which often grinds away under the chisel, instead of splitting off.
THE STRAWBERRY CRAB.
Among the multitudes of curious creatures which the dredge rakes up from the prolific bottom of Weymouth Bay there occurs occasionally a pretty little Crab, which is sometimes called the Strawberry, from its being studded all over with pink tubercles on a white ground, remotely resembling the seeds that adhere to the fleshy surface of that delicious fruit. The same peculiarity has been seized to give its scientific appellation, Eurynome aspera. These tubercles under a low magnifier are very curious, consisting of short cylindrical columns, the truncate ends of which are beset with polished red or white hemispherical knobs, The first pair of legs have the joints very long, projecting awkwardly in an angle on each side, and the wrists have a curious twist.
Mr. Bell in his beautiful work on the British Crustacea, calls this one of our rare species, and says that little is known of its habits. I am the more pleased to have an opportunity of adding an item to its history, and of tracing some connexion between its habits and the peculiarities of its conformation.
The story may be summed up in a word; the Strawberry Crab is a climber. If it were a terrestrial animal, I should say its habits are arboreal. True, it now and then wanders over the bottom of its abode, with slow and painful march, the hind feet held up at an angle above the level of the back; but generally it seeks an elevated position. We usually see it in the morning perched on the summit of some one of the more bushy weeds in the Aquarium, as the Chondrus or Phyllophora rubens, where it has taken its station during the night, the season of its chief activity, as of most other Crustacea. It interested me much to see it climb: seizing the twigs above it by stretching out its long arms alternately, it dragged up its body from branch to branch, mounting to the top of the plant deliberately, but with ease. While watching it I was strongly reminded of the Orang-otan at the Zoological Gardens; the manner in which each of these very dissimilar animals performed the same feat was so closely alike as to create an agreeable feeling of surprise.
This circumstance led me to think of another; the resemblance was not only in habit, but in conformation also; viz. in the great length of arm. This is obviously an adaptation for climbing in the Quadrumane as well as the Crustacean; and a few examples occured to my remembrance in which a similar structure is associated with the like habit. All the Monkey tribe, for instance; and the Sloths of South America, which are almost exclusively arboreal, have the anterior limbs excessively long. Many of the Longicorns among beetles are remarkable for their developed arms, and these are essentially tree-insects. Again, among the Spiders, the perpendicular web-makers as Epeira, Tetragnatha, &c., which run to and fro on the tracery of their slender lines, like seamen manning the shrouds on a fleet gala-day,—have the anterior legs much elongated; while the genera which live on the ground or on fixed objects, as the great hairy Spiders (Mygale, Cteniza, &c.), the Wolf Spiders (Lycosa), and the Jumpers (Salticus, &c.), have the legs very short. Perhaps this parallel might be much extended; at the same time I must confess the rule is not without exception; as witness the arboreal Squirrels, whose fore limbs are sufficiently short.
THE CLOAK ANEMONE.
Among the singular disguises by which familiar objects are sometimes rendered difficult of identification, not the least interesting are some that arise from the association of creatures very remote from each other in structure, habit, and zoological position. Many persons who know a Whelk as well as possible, hesitate when they see the familiar shell tenanted, not by the great black-spotted Mollusk, but by a mongrel between Crab and Lobster, with stout, red, pinching claws, and long, jointed, and pointed legs. And still more mysterious does the thing look, when two thirds of the shell itself is enclosed in a thick mass of purple-spotted flesh, through the midst of which the busy Crab is poking his head and limbs. In truth it is a strange affair, this threefold alliance of Whelk, Hermit crab, and Cloak-anemone.
Let me describe the last a little more particularly; it is the Adamsia palliata of zoologists. All round the mouth of the shell is firmly adhering a soft but firm pulpy mass of flesh, of which the upper part is commonly of a warm brown hue, but the under surface is delicately white, dotted over with round spots of rosy purple. I have said it adheres around the shell-mouth; and this is a curious circumstance, because, as it does not extend across the orifice, the animal assumes an annular form, the Crab inhabiting the shell, and protruding freely through the opening. On that side which is next the inner lip or column of the shell, and beneath the breast of the Crab, there opens a wide oblong mouth, in all essential particulars like that of an Actinia, surrounded by a delicate fringe of short white tentacles; which in general are freely exposed, seeking for prey; the animal being little alarmed by the rude treatment to which the peregrinations of its active companion expose it.
This form, at first sight, seems so very anomalous, that a naturalist of no small knowledge has recourse for its explanation, to the suggestion "that the old shell [of a Gasteropod Mollusk] with a young Crab in it may have been swallowed by the Actinia; that the Crab may have forced its way through the walls of the stomach and the integuments of the latter, and that the Actinia then secreting a peculiar membrane to defend its base, the Crab may have found itself provided with a habitation suited to its wants."[1] Yet it appears to me that the deviation from normal structure is more apparent than real. The Adamsia is evidently an Actinia of a long-oval form, capable of development in its long diameter into two lengthened wings. Its instinct invariably leads it to select as its support the inner lip of some univalve shell, having adhered to which, the lateral expansions creep along the shell, following its surface until they have surrounded the aperture, and meet each other on the outer lip. Here the meeting edges unite by mutual adhesion, and seem to grow together, yet the suture is always distinctly visible, both by a slight depression, and by a pale line which assumes a zigzag form, owing to the terminations of the body striæ fitting into the interspaces of the opposite ones.
What is curious in the case is the instinct which makes the Adamsia select a shell as its constant support, and the association with it of a Hermit Crab as the co-tenant of the same shell. This association is I think constant; for though the dredge does occasionally bring up shells invested by the Adamsia, which are empty, yet I incline to believe that these shells have been recently vacated by the tenant Crabs, and not that they have never been so occupied at all.
That the above is the correct explanation is evident from specimens in various stages of development. There is in my possession, while writing this note, an Adamsia, adhering to a Whelk, of which the lateral lobes, though projected around the edges of the mouth of the shell, have not yet met each other on the outer lip, but are separated by a space of a quarter of an inch. And my friend Mr. Thompson, whose opportunities for studying the marine animals of Dorsetshire, have been most zealously improved, has just showed me a very young specimen, not larger than a silver three-pence, in which the side lobes were not in the least developed. This specimen had selected a land shell as its support, a not quite adult Garden Snail (Helix aspersa), within which a Pagurus Prideauxii had taken up his abode also. The Adamsia was prettily spotted, though so young; its position was as usual the inner lip of the shell. This, curious specimen, interesting on more than one account, was dredged in 8 fathoms off Whitenose in Weymouth Bay, a mile or two from land, on the 12th of September, 1853. It lived in captivity five days.
My notion is further confirmed by what takes place in the disease and death of the animal. When the Crab deserts the shell or dies out, the Anemone for a while expands as usual. But after a week or two, it is evidently seen to be languishing; and soon its adhering base begins to peel off and shrink away from the shell. Now this process commences at the suture, and as it goes on the suture divides, the lateral portions separate more and more from each other, by skrinking; reversing exactly the steps by which the annular habit was assumed, and which I have described above. At length, the connexion of the animal with the shell is wholly dissolved, and the former collapses into a shapeless lump of flesh, from which the integuments slough away in gelatinous shreds, and the whole swiftly becomes a putrescent mass.
Since the above was written, Mr. Thompson has favoured me with an account of an Adamsia so aberrant in its habit as to require a modification of the statement that a shell is always chosen. My friend writes as follows:—"I have lately obtained a specimen of Adamsia palliata, dredged in three fathoms' water, on a frond of Fucus serratus. It is round and united, but with a suture down one side."
A curious evidence of the efficiency of the thread-capsules as weapons of offence has occurred to me. I was examining the brilliant purple filaments of Adamsia palliata, under a power of 200 diameters. There was no pressure applied, but a considerable number of the small capsules were spontaneously dislodged. In the aquatic box which I was using there was, still affixed to one of the glasses, the sucker of a Gibbous Starlet (Asterina gibbosa) that I had just before been looking at. The ciliary action of the Adamsia's filament had been wheeling it round and round, partly in contact with the sucker, and the result was that a good number, (a dozen or two at least) of the thread-capsules had shot their darts into the sucker, and were seen sticking all around its edge, their threads imbedded into its substance, even up to the very capsules. I thus saw how readily these barbed threads are projected into the flesh of any offending animal; and if they are accompanied, as is probable, by a subtle poisonous fluid, they are doubtless very effective.
The filament under pressure shows thread-capsules in innumerable millions, forming the greatest part of its substance. This immense number is probably intended to meet the continual demand for the use of the weapons during the life of the animal; since, once shot, the thread sticks in the wounded flesh, and carries the capsule with it; while, if it fail to strike I suppose it can never be recoiled, and re-inclosed.
The filaments, which are of the same rose-purple hue as the spots, are excessively abundant in this species, and are projected on the slightest disturbance of the animal. The firmness with which they adhere to the fingers when accidentally touched, so that it is a difficult matter to clear them away, proves that even the most callous parts of the human skin offer no impediment to the entrance of those subtle weapons, the barbed threads, though their poisonous properties are too feeble to be appreciated by our nerves.
THE PARASITIC ANEMONE.
This species (Actinia parasitica of Couch) takes rank among the largest of our native Actiniæ, being only exceeded by fine specimens of A. dianthus. It frequently attains a height of four inches, and a diameter of two and a half. It is of a columnar form, nearly equal in diameter throughout, but commonly a little expanded at the base, which slightly spreads over the substances to which it adheres.
The colouring of the body, though subject to some variation, always maintains such an uniformity of style and pattern as to render it easy of identification at all times. Indeed I know of no species which is less liable to be mistaken for any other than this. The ground-colour is a dirty white, or drab, often slightly tinged with pale yellow; longitudinal bands of dark wood-brown, reddish, or purplish brown, run down the body, sometimes very regularly, and set so closely so as leave the intermediate bands of ground-colour much narrower than themselves: at other times these bands are narrower, more separated, and variously interrupted or broken. I have seen a variety in which the bands took the form of chains of round dark spots, the effect of which was handsome. Immediately round the base the bands usually sub-divide and are varied by a single series of upright oblong spots of rich yellow, which are usually margined with deeper brown than the bands. The whole body is surrounded by close-set faint lines of pale hue, sometimes scarcely distinguishable, except near the summit, where they cut the bands in such a manner as to form, with other similar lines which there run length-wise, a reticulated pattern.
Towards the lower part of the body numerous warts appear, mostly minute, but a few among them are large and prominent. The body terminates above in a slightly thickened rim, which is minutely notched, but scarcely rises above the level of the disk, and is obliterated when the tentacles are fully expanded.
The disk is somewhat wider than the diameter of the body, which it over-arches on all sides. Its margin is somewhat thin, and occasionally thrown into puckered folds to a small extent. Thus it appears to approach the peculiar form of A. bellis. The disk is nearly flat or slightly hollowed, but rises in the centre into a stout cone, in the middle of which is the mouth, edged with crenated lips. The tentacles are arranged in seven rows, of which the innermost contains about 20, the second 24, the third 48, the fourth 96: the other rows are too closely set and too numerous to be distinguished. Probably the whole number of tentacles in a full grown specimen may be considered as certainly not less than 500. The innermost row springs from the disk about midway between the lips and the margin; they occasionally stand erect, but more frequently arch outwards in elegant curves. When distended with water these are often an inch in length, and 18th of an inch in thickness; the others diminish in regular gradation until those of the margin do not exceed 110th in length and a proportionate diameter. All the tentacles are of the same form; though this varies a little in different specimens, sometimes being blunt and nearly cylindrical, at others gradually tapering and drawn out to a fine point. They are pellucid, faintly tinged with flesh-colour, cream-yellow, or purplish, each one being always marked with from one to five pairs of lines or dashes of a dull-purplish colour, running down the two opposite sides to the tip. Those rows which form the marginal fringe are frequently divided into alternate patches of colour, a patch of pale tentacles, then one of purplish, six groups of each colour completing the circle. These alternations do not conceal the lateral marks of the tentacles, and though sometimes beautifully distinct, they are at others scarcely perceptible.
The surface of the disk is pellucid yellowish-white, marked with a circle of six squarish patches of opaque white, corresponding to the lighter portion of the marginal fringe: the lips are also opaque white.
This fine and very distinct species is exceedingly abundant in Weymouth Bay, extending from the deep water of the offing, even into the narrow harbour; but is never met with between tide-marks. It is, as its name imparts, parasitic in its habits, though not so strictly but that we frequently find specimens adhering to stones; and in captivity it is by no means uncommon for an individual to detach itself from its native site, and adhere to the bottom of the vessel, or even to crawl a little way up the perpendicular side. Generally, however, it is found embracing some univalve shell, which is tenanted by a Soldier Crab; young specimens on Turritella terebra, Trochus magus, T. ziziphinus, &c., but adults, which are much more frequently met with than the young, almost invariably on the great Whelk (Buccinum undatum). The dredge indeed often brings up shells invested by the Actinia which are empty; but I believe that in every such case, the shell has recently been vacated by the soldier, and that the Actinia never voluntarily selects an empty shell for his base.
The crab who sustains the honourable office of porter to this species is invariably Pagurus bernhardus, as P. Prideauxii is favoured with the support of Adamsia palliata.
In the rude and blundering manner in which the bearer performs his office, it cannot be but that the poor Actinia gets many a hard knock, and many a rough squeeze, among the rocks and stones over which his servant travels; but he appears to bear these mischances with great philosophy: I know of no species which lives so constantly expanded. A rude shock will indeed cause it to withdraw its tentacles, and contract its disk into that button-like shape which is common to the genus; but this is only for a moment: it instantly expands again and remains full blown in spite of all its draggings about. Its skin also is peculiarly tough and leathery; a provision, doubtless, against the accidents to which its vagrant life exposes it.
We have no species which to such an extent as this shoots forth those white filaments, which in this family are weapons of offence, On being alarmed or rudely handled, from several of the warts on the body the animal shoots forth these threads, which exactly resemble white sewing-cotton, to the length of four or even six inches; and under circumstances of great irritation an immense bundle of such threads is projected from the mouth. These filaments are not wasted: they are shot out in a straight line, but remain attached to the animal, and presently all trace of them has disappeared. They are withdrawn again into the body.
This curious result, which I did not anticipate, I proved by carefully watching the process with a lens. The naked eye can readily perceive that each thread is gradually corrugated into small irregular coils at that end which is next the animal, while the free end remains straight. By applying a pocket lens with a power of 15 diameters to the affixed end, I perceived that it was sucked in to the wart from which it had proceeded, the orifice of which was clearly visible. Fixing my attention on some part of the thread near the wart, I saw it rapidly approach, and at length disappear within its cavity, and the same process went on constantly, and with all the projected threads together, until all were retracted.
These threads have, I feel assured, no direct connexion with the generative function; they are weapons of offence, and very effective ones. The fatal effects produced by their adhesive contact upon a little fish I have already described (vide ante, p. 115). Their power of adhesion is remarkable, and must have been felt by every one who has handled the species with the fingers; they cling around the flesh with the most annoying tenacity, so that it is no easy matter to cleanse one's hand of them. In what resides this adhesive power? Doubtless in the barbed threads which are sheathed in innumerable myriads in every filament. The force with which these javelins are projected, their elastic strength, and their excessive tenuity enable them to penetrate animal tissues, even of apparently dense texture; and their barbed bristles enable them to maintain a firm hold. On this matter I beg my reader's reference to the note on the filaments of Adamsia, in p. 143.
Under the compressorium the thread suddenly cracks, with a start and a crepitation distinctly audible; a curious circumstance, which seems to indicate a crustaceous or siliceous structure somewhere. I think it cannot be the walls of the filament itself, but the capsules, that crack, minute as they are. The filament is more densely filled with capsules than that of any species which I am acquainted with: perhaps there are even millions of them. The capsules are of about the average size of those found in other Actiniæ; viz. 1875th of an inch in length, and of the ordinary form, linear-oblong, almost straight; the contained thread is propelled to no great length, in some cases scarcely exceeding that of the capsule, in others reaching to five times the length; or from 1700th to 1175th of an inch. A slight thickness is discernible about the basal half, which indicates an armed furniture, but I was unable to resolve its precise structure.
A rank penetrating odour proceeds from this species, in a greater degree than usual. It is communicated to the hands by handling; and repeated washings with soap, and even scrubbings with a brush, scarcely avail to remove it. It is insufferably nauseous.
In the accompanying picture the centre is occupied by this Anemone, seated on the shell of the common Whelk. From the same shell springs a branching zoophyte, Sertularia abietina, while a Brittle-star (Ophiocoma rosula) is creeping by means of its long snake-like arms over the lower part. Behind the Actinia are seen three or four leaves of that lovely sea-weed, Delesseria sanguinea; a tuft of Callithamnion roseum springs from a crevice in the rock above the Sertularia; a patch of the velvet-like Call. Rothii is seen on the stone in the foreground, and one of the mossy C. spongiosum in the rear. In front of this last are some young leaves of Rhodymenia palmata, and a frond of the same species is growing on the shell of the Whelk.
- ↑ Coldstream, in Johnston's Brit. Zooph. i. 209.