Part 2

It is one of our showy shells. This specimen before us has for its ground colour a chaste, cool grey, occasionally varied with tints of reddish buff, but most conspicuously adorned with a series of large and regular spots of purplish crimson running along the lower angle of the spire from the base to the summit. Each of these spots passes off into an oblique line above, the repetition of which augments the beauty of the pattern.

The interior of the shell has a glory of quite another character. It is covered with a coat of nacre or pearl, of exceedingly brilliant and rich lustre, and the presence of this inward pearliness is quite characteristic of this genus, and of most of the others belonging to the same family, the _Turbinidæ_. Many of the fine large tropical species are specially conspicuous for this adornment, as I have seen in those that lie along the dazzling beach of coral-sand in lovely Jamaica. The pearl of these shells is used in the arts. De Montfort mentions a necklace which he had seen, that was made out of the nacred part of the shell of the _Turbo smaragdus_, and which was _much more brilliant and beautiful_ than any of the finest orient pearls.[3] And Chenu observes:--“Les grandes espèces fournissent une fort belle nacre, employée pour les ouvrages de marqueterie. Quelques espèces ont reçu des noms sous lesquels les marchands les distinguent: il y a le Burgau ou Nacré; la Veuve Perlée, dont les tubercles extérieurs usés ressemblent à des perles; la Bouche-d’Or, dont la nacre est d’un beau jaune doré; la Bouche-d’Argent; le Perroquet, ou Turbo Impérial,” etc.[4]

At another time we may examine the structure of shell, and inquire by what instruments and with what materials the ingenious animal contrives to construct so strong and so elegant a dwelling. For the present, however, as the month is January, we shall, if we sit still longer, run the risk of “catching a cold,” if we catch nothing else, though the wind _is_ in the south, and the temperature is so mild for the season.

THE DOG-WHELK.

Therefore, we will move about and pursue our researches among the rocks and under the loose stones. Well, we are rewarded with other specimens: here are several neat little shells, with a lengthened spire, and with a remarkably thickened lip. This is the little Thick-lipped Dog-whelk,[5] a very common mollusk with us under such stones as these at low water-mark. And here is another species of the same genus, the Netted Dog-whelk,[6] which is a much larger shell, being nearly twice as long as the former, and marked with close transverse furrows, which, crossing the longitudinal ribs at right angles, give a peculiar reticulate surface, on which the specific name is founded.

Comparing these shells with the _Trochus_, we see that they have a deep notch cut in the front part, of which no sign appears in the latter; and this mark, trivial as it may seem, is an important indication of the habits of the animal. The inhabitants of all shells which have this notch are carnivorous, while those with simple lips are herbivorous. The _Trochus_ gnaws or rather rasps away the tender growth of marine vegetation, or the fronds of the grown _Algæ_, with its remarkable palate-ribbon, all studded with reversed points, of which I may find another opportunity to speak. The Dog-whelk, on the other hand, acts the part of a cannibal ogre, feeding on his simpler brethren of the bivalve shells; storming their stony castles, in which they seem so secure, by open violence.

Look at this old valve of a _Mactra_. Like hundreds more that you may pick up at high water-mark, it is perforated by a tiny hole near the hinge, so smooth and so perfectly circular, that you would suppose a clever artisan had been at work drilling the massive stony shell with his steel wimble. No such thing: the Dog-whelk has done it: this is the breach which he so scientifically effected in the fortress; and hence he sucked out the soft and juicy and savoury flesh of his miserable victim.

In order to understand his plan of operations, let us put down our captive, and see him crawl. He is not long before he begins to march, on his broad oblong foot, which, as you observe, is cream-coloured, elegantly splashed and speckled with dark-brown. But before he moves he thrusts out a long cylindrical proboscis from the front of his head, which he carries high aloft and waves to and fro; and this organ, we see, fits into the deep notch in front of the shell. This proboscis is his drilling-wimble.

THE DOG-WHELK’S DRILL.

This organ is itself a study. Long as it is when extended, it can be thoroughly drawn within the body; and there it forms two fleshy cylinders, one within the other, exactly like a stocking half turned on itself. There are proper muscles attached to its walls, and to the interior of the head, by extremities which are branched in a fan-shape, so as greatly to strengthen their insertions; and these, by contraction, draw the one portion within the other. Then there is a broad hoop of muscle, which, passing round the inner cylinder, by contracting pushes it out, and lengthens it. Within the interior of this latter there is a long narrow ribbon of cartilage, which is armed with rows of sharp flinty points, turned backwards; and this tongue or palate, as it is variously called, is the Dog-whelk’s weapon.

We cannot induce the Whelk to attack his prey just when we please; but he has been detected in the operation, and I will describe it. With his broad muscular foot he secures a good hold of the bivalve, and having selected his point of attack, in general near the hinge--a selection which probably looks more at the superiority of the meat within than at any peculiar facility in the perforation--he brings the tip of his extended proboscis to the point, so that the silicious teeth can act on the shell. Hard as is the calcareous shell, it is not proof against the flint; for, without any solvent excretion, the aid of which some physiologists have been ready to suppose, these glassy points, grating round and round as on a pivot, soon wear away the substance, and gradually bore the tiny aperture which exposes the sapid morsel.

Continuing our researches, we find, deep in a rocky pool under a tuft of weed, a shell of a peculiar form, because of the enormous expansion of its outer lip. It is known as the Pelican’s-foot,[7] from the resemblance which this lip with its diverging ribs bears to the webbed toes of a water-fowl. This, too, is a carnivorous species; and though it is somewhat rare to detect the animal moving, even though kept alive in captivity, yet by carefully examining this one in its deep pool, before we disturb its equanimity, we can just see the proboscis protruding from the wide square notch in the shell, and discern that it is rather prettily coloured, being marked with spots of opaque white on a rose-coloured ground.

This species is interesting from the changes of figure which it undergoes in its progress from youth to maturity. While young the shell is simple, with no trace of the expanded lip; and it is only at mature age, and rather suddenly, that the shell makes its remarkable growth into these far-projecting points and angles, the augmented thickness of which is, moreover, at least equally conspicuous with the expanse.

THE COWRY.

But far more remarkable changes take place in the growth of the shell in a family of signal beauty, of which I discern a specimen in yonder cavernous hollow. The family I speak of is that of the Cowries; and this individual represents the only species that is indigenous to our seas--the little Furrowed Cowry.[8] Let us pause awhile to admire it, for it is one of the very loveliest of our marine animals.

The shell itself is doubtless familiar to most of my readers, for it is to be picked up on every sandy beach. It varies in size from that of a split pea to that of a large horsebean. It is elegantly marked all over with transverse ridges. These ridges are porcellaneous white, and the alternate furrows between are purplish, or flesh-coloured. The larger specimens commonly display three spots of dark brown, arranged lengthwise. But probably few are aware how very elegant a creature it is when tenanted by its living inhabitant, and crawling at ease in clear water. The foot, on which it glides with a slow but smooth motion over the surface of the rock on which it habitually dwells, or, if you please, on the bottom of the saucer of sea-water in which you are examining it, is a broad expansion spreading out to twice the superficies of the base of the shell. Above this is the fleshy mantle, which is so turned up as closely to invest the shell, conforming to its shape, and even fitting into the grooves between the ridges. This mantle can be protruded, at the will of the animal, so far that the two sides meet along the top of the shell, and completely cover it, or it can be completely retracted within the wrinkled lips beneath; and it is capable of all gradations of extension between these limits. From the front of the shell protrudes the head, armed with two straight and lengthened tentacles, answering in function and appearance to the upper pair of horns in a snail; except that the little black points which constitute the visual organs are not in this case placed at the tips, but on a little prominence on the outside of the base of each tentacle. Above and between these, which diverge at a considerable angle, projects the proboscis, a rather thick fleshy tube, formed by a flat lamina, with its edges bent round so as to meet along the under side. The interior of this proboscis is lined with delicate cilia, by whose constant vibrations a current of water is drawn into the tube and poured over the surface of the gills, for the purpose of respiration. This current may be readily perceived by any one who will take the trouble to watch, with a pocket-lens, a Cowry crawling along the side of a phial filled with sea-water. By placing the vessel between your eye and the light, and fixing your attention on the front of the proboscis, you will presently perceive the minute particles of floating matter (always held in suspension, even in clear water) drawn in various directions towards the tube, with a motion which increases in velocity as they approach, and at length rapidly sucked in, and disappearing one after another within. It is an interesting sight to see, and one that cannot be looked on without delight and admiration at this beautiful contrivance of Divine Wisdom, for the incessant breathing of the respiratory organs in water charged with vivifying oxygen.

Let us look at the vivid hues of all these organs. The foot, which expands to so great a length and breadth behind the shell, is of a buff or pale orange ground-colour, delicately striated with longitudinal undulating veins of yellowish white. The mantle which embraces the shell is of a pellucid olive, thickly mottled and spotted with black, and studded with glands protruded through its substance, of light yellow; and is often edged with a narrow border of red. The proboscis is vermilion-red, varying in brilliancy in different individuals. The tentacles are of a paler tint of the same colour, speckled with yellow.

Such, then, is the beauty of the animal which inhabits this familiar and plain little shell,--a beauty of which those who know it only in cabinets can hardly form an idea; while, as the observer gazes on it placidly gliding along, he cannot avoid an emotion of surprise that such an amplitude of organs can be folded within the narrow compass of the shell, and protruded through so contracted an aperture.

THE SCALLOP.

You would scarcely recognise in this shell, or in the Tiger Cowry, that one so often sees on chimney-pieces, the model of an ordinary convolute spiral shell, such as the snail or the whelk. But in infancy and youth the Cowry is a shell manifestly of such a character, scarcely to be distinguished from the Olives and Volutes; a shell with a distinct spire, a long wide aperture, and a thin-edged outer lip. But when the animal has arrived at mature age, a sudden deposition of shelly matter takes place on the lip, which is greatly thickened, and which expands above so as to conceal the spire, bending inward at the same time and approaching the inner lip, so as to reduce the aperture to a very narrow line. Finally, a thick coat of enamel, or glossy porcellaneous lime, is spread over the entire surface of the shell, from the narrow aperture to the back-line, which coat takes the form of those transverse folds which are so characteristic of the species and so elegant.

Here, clinging to the perpendicular wall of rock, sheltered snugly by an overshadowing stone, which I have just removed, is a lovely specimen of the Squin or Scallop.[9] In the ages of monkery, when men’s eyes were more directed to the land where the blessed Lord Jesus once sojourned than to the place where He now is, and pilgrimage to an earthly country was more valued than that to a heavenly, this shell affixed to the hat was the accepted sign that the wearer had visited Jerusalem; and received the homage of sanctity that such a pilgrim claimed.

“He quits his cell, the pilgrim staff he bore, And fixed the scallop in his hat before.”[10]

Some mystic connexion, some secret sympathy, was assumed to exist between the scallop and St. James, the brother of the Lord, first bishop of Jerusalem. What it was appears to be irrecoverably lost in the darkness of those very dark ages, and is doubtless not worth the hunting up. We may leave such puerilities, to consider the impress of His divine hand which the All-wise God has made on the shell of the mollusk that inhabits it.

These bivalves have been called the “butterflies of the sea,” as well on account of the vivid and varied colours with which their broad wing-like valves are painted, as of their agile fluttering and flying movements. We frequently see them, especially for some time after having been taken and put into an unfamiliar scene, as our aquariums, shoot hither and thither through the water, with irregular zigzag flights, accompanied with fitful openings and closings of the valves. These leaps and flights seem to have no determinate object, except “the letting off the steam” of their exuberant animal vivacity; but the creatures have the power of directing their leap by a forcible ejection of water from any given part of the compressed lips of the mantle.[11]

THE SCALLOP’S EYES.

It is a very pretty sight to see a healthy Pecten in a vessel of clear sea-water. The elegant valves are opened to a considerable width, perhaps to half an inch or more, and the entire aperture all round is filled by a curtain, which drops from one to the other, perpendicularly, a little way within the margin. This is the mantle, and it is generally painted with rich colours, in irregular patterns, often of spots and marbled clouds of black on a rich green ground, or pearly-green clouds on flesh-colour--sometimes pale-yellow clouds on velvet-black; but these hues have no perceptible relation with those of the shell. Looking closely, you see that the mantle is not single, but composed of two curtains, whose edges meet in the middle. And now these are slightly separating, and giving us a peep into the interior; but the most notable thing we see is the array of long white taper tentacles which proceed from each edge, and wave to and fro in the clear water; while another row of similar organs, but larger, is affixed to each curtain along the line where it starts from the shell. And along this same line, scattered between the bases of the larger tentacles, there is a row (and a corresponding one on the other curtain) of beads, which seem to be turned out of the richest and most lustrous gems. Even the unassisted eye is arrested by the flashing brilliance, but with a powerful lens they look like rubies set in sockets of sapphire, from which the light blazes forth with incomparable brilliance. These are the Pecten’s eyes, each of which possesses all the parts requisite for perfect vision.

The valves vary much in colour. Some are pure white; some white with a crimson line along the summit of each radiating ridge; some rosy, crimson, or lilac; some cream, straw-yellow, deep yellow; some dull brick-red, dark purplish-red, or sienna-brown; some are marbled with black on a red ground, making a very rich pattern.

The largest specimens, and those with greatest variety in hue, are found in deep water, and for the most part congregated in large numbers on some particular spot of the sea-bottom, which is called a scallop-bed. Such are found in Weymouth Bay, and in Torbay; and there the shell-fish can be obtained in sufficient quantity for the market. At Weymouth there is a considerable business done in these delicacies, which is, however, almost all in the hands of one dealer, from whom I have collected some details of interest.

The ordinary trawlers avoid the scallop-beds, if possible, because they are liable to have their nets torn by them; the sharp valves doubtless catching and cutting the meshes. But they often bring up many unintentionally, and a naturalist would find a trawler’s refuse a most productive field: for numbers of rare and valuable zoophytes and other forms of life come up attached to the shells, which might easily be saved, but are not: the men “have no time, for they are so anxious to get their craft into a berth, and then to take out the fish as soon as the trawl is up.”

Twenty bushels of scallops are sometimes taken at once; but this is rare. The average produce of the Weymouth trawlers is five bushels per week, which are readily sold at twopence per hundred; about seven hundred going to the bushel. The customers are “mostly the genteels,” who eat the _morceaux_ stewed with flour or scolloped. The worthy woman who commands the supply had had the trade in her hands for twenty-eight years (in 1853); she had never heard them called by any other name than “Squins,” though she understood they were called Scallops in some places. “Squin” is by some said to be a corruption of “Quin,” after the actor and epicure of that name, who is reported to have been fond of the delicate mollusk; but I much doubt the derivation.[12]

As a proof of the tenacity of life possessed by this species, a fisherman assured me that he once put a quantity in a bag into a cupboard and forgot them, till, after the lapse of a week, turning them out he found them alive.

THE SEA-CUCUMBER.

But now another object of interest claims attention: for, in this cavern, closely squeezed in between the layers of stone, I see the satiny-white skin of a glorious Sea-cucumber. And now to get him out, there’s the rub. So firmly imbedded is he, so deeply ensconced, that no pushing with fingers or sticks will avail; indeed, I can but just touch his body with my finger-ends poked in to the utmost. No; we must cut away the rock above and below with the strong steel chisel, by means of well-directed strokes of a heavy hammer. Slow work it is, for the rock is awfully hard: the prize, however, cannot escape, and the chief point of solicitude is not to crush it in the process. At length a fortunate blow splits off a slice of rock, which leaves the unhappy skulker defenceless. Now I get my fingers gradually behind him, and force him out, gently and tenderly; sucker after sucker he is compelled to let go, and now here he is in my hand, shrunken indeed, and squeezed flat from his very shrinking in the close crevice, but all unbroken and none the worse.

This is a much more sluggish creature than any of the mollusks that we have been capturing: no sooner are they put into water than they are active, and at once display their attractions; this animal, on the contrary, will be perhaps several days in your tank before he will feel himself sufficiently at home to unfold his splendid array of tentacles. But then it is indeed a magnificent coronet of plumes wherewith the headless king is adorned.

The Sea-cucumber soon finds himself a snug berth among the rock-work of the tank; pressing his body between the pieces just as when we saw him first, but taking care to leave space to protrude his front. Then this part evolves, and a deep collar of dark purple is seen, from which a ring of ten somewhat thick stems arises, tapering to a point and arching outwards. These are of a purplish-black hue, and are studded with short branches set on in a spiral, which again branch and branch again, each terminal point bearing a white papilla; so that the whole constitutes a series of conical aggregations of white dots clustering about the black stems, something like pointed cauliflowers, and forming, as they wave to and fro in the clear water, a very charming spectacle.[13]

The suckers, which, when the animal first came into our possession, were apparent only as little warts, arranged in five clustered rows down the angles of the body, are now seen to be long tubes, each with an adhering disk at its extremity, by which it anchors to the surrounding stones. The mechanism of these suckers does not importantly differ from that of the same organs in the Star-fishes. Indeed, notwithstanding the very wide diversity of form and appearance between the two animals, the Cucumber and the Star are so nearly allied as to belong to the same class, that named ECHINODERMATA; the Sea-urchins, creatures totally diverse in aspect from both, connecting the forms together.

And this Cucumber, again, is connected with the proper worms (ANNELLIDA) by some obscure animals which bear the name of Siponcles. Here is one which may illustrate the form, the Dotted Siponcle.[14] It has a cylindrical body, rounded and abruptly pointed behind, which is of a light-brown hue, with a satiny gloss; but the hue resolves itself under a powerful lens into a freckling of pale dots, excessively numerous, on a brown ground, and the lustre into a multitude of close-set annular wrinkles. What is curious in the creature is the protrusion and retraction of its trunk. From the front end of the body we see rapidly protruding, by evolution of the parts, a rather slender trunk, till it attains about one-third the length of the body; then its tip expands, and is seen to be surrounded by eight rows of black points, and within these a circle of slender, white, thread-like tentacles. These latter are the representatives of the gorgeous head-plumes of the Cucumber. Immediately the long trunk is turned out to the outmost, it begins to be rolled in again; and this process goes on with equal rapidity till it is quite concealed. Then again it is unrolled, and so on alternately. Doubtless the function of respiration is performed by this action; and perhaps also food is collected and swallowed.

THE HERMIT SIPONCLE.

One species of this creature, the Hermit Siponcle,[15] common enough with us, is in the habit of appropriating old deserted shells of univalve mollusca, as the periwinkle, or the pelican’s-foot, for its own residence. In this case it builds up a wall of sand-atoms, cemented by a glue of its own secreting, across the shell-aperture, leaving only a small central orifice, through which it may protrude its curious trunk.

Thus we discern the infinite and inexhaustible resources of the Divine Wisdom in contrivances which have for their object the preservation, sustentation, and comfort of worms so obscure and humble as these. Discerning, let us adore!

FOOTNOTES:

[1] _Trochus ziziphinus_, which the reader will see figured in the upper right corner of Plate I.

[2] _Phasianella pullus._

[3] _Conch. Syst._ ii. 252.

[4] _Leç. Elém._ 188.

[5] _Nassa incrassata._