VIII.

'Barnacles turn Solan GeeseIn the islands of the Orcades.'

Ifthe reader has been struck at what has been said in regard to the exuviation of crabs, &c., he will probably be more surprised when I state that precisely the same phenomena take place in the simpleAcorn Barnacle, that studs in countless numbers almost every rock and shell situated between tide marks. No one can visit the sea-shore, at certain localities, without noticing the white spots which constitute the shells of the cirripeds in question, although he may not be acquainted with the marvellous beauty of the animal contained within each.

Its loveliness, it is true, is in no wise apparent when parched and dry; but let the welcome waves advance and playfully dash their spray against the dwelling of the little crustacean, and quickly its valves will open, displaying a delicate feathery plume, thrust forth and hastily withdrawn again.

As it is not convenient to watch the movements of this animal in a rock-pool, let me request the reader kindly to take a peep into my aquarium.Here is a Trochus shell, for example, inhabited, as you perceive, by a Soldier-Crab, the surface of which is thickly covered with shelly cones, of small dimensions. These are the Barnacles (Balani). The Trochus most fortunately being near the side of the glass, is capitally situated for our purpose. Take the hand lens, adjust its focus, and watch carefully for the opening of the cones. Tush! The hermit neverwillrest contented in any position for two consecutive minutes; but see! as he walks away the fairy hands are being rapidly thrown out and made to sweep the water in graceful curves, thereby suggesting some resemblance to a bevy of school children at Christmas time, biddingadieuxto their friends, while seated on the roof of an old stage coach.

Carefully I lift the Pagurus bodily out of the tank, and transfer him to a wine glass filled with clean water. After a few minutes have elapsed, the hands again commence their fishing operations. Observe, now, that these organs fan the fluid in such a manner as to catch any animalculæ that may be near, and draw them towards the aperture caused by the opening of the valves of the Barnacle. A close inspection will, I am sure, prove to your satisfaction that there is also distinctly apparent a second and smaller cluster of feathery fingers, whose duty it is to catch the food, brought near by the larger and corresponding organs, and finally convey it into the mouth of the little cirriped. There maybe, in the wide range of Nature's lower scale of life, prettier sights to gladden the eye of the student than that above described,—but if so, I must confessmyinability to indicate where such are to be found. The fishing apparatus here mentioned consists of a number of slendercirri, thickly coated with microscopic filaments (cilia), and is, at certain periods, thrown off complete and entire by the process of exuviation, just as we have seen it occur in the higher crustacea.

Would you, my young friend, like to procure an exuvium of the Barnacle for examination? Yes. Then follow the directions I am now about to give, and your wish will be speedily gratified.

Presuming that your tank already contains a number of Barnacles attached to various objects, and that such have been in the same vessel for some weeks; syringe the water for a few minutes, and you will find floating about, or rising to the surface, many specimens of the desired object. They will, in all probability, be visible to the naked eye. To attempt to lift one out of the water, however, by means of your finger and thumb would be utterly useless. Such a procedure, even were it successful, would inevitably mar the delicate beauty of this 'inessential' object, which, spirit like, casts no shadow upon weed or water. The best plan is to insert a tube of glass into the aquarium, in such a way that the exuvium may ascend the interior. Then placeyour finger on the top, and draw the tube out of the water, and you will be able to deposit the skin of the Barnacle upon a slip of glass by merely lifting off your finger. The specimen can then be leisurely arranged, and spread out by aid of a hand lens and fine pointed needles.

Walking by the sea-shore one fine summer afternoon, I met a fisher boy running along with some curious objects spread out in the palm of his left hand, while in his right, suspended from finger and thumb, appeared a still more desirable prize.

At first glance I detected the objects to be specimens of theLepas anatifera. They had, so the boy stated in answer to my inquiries, been plucked from the base of a ship newly arrived from a long voyage. When I offered him sixpence for the 'lot,' the embryo plougher of the deep looked up in my face with a singularly mistrustful expression, and said, 'D'ye mean it, sir?' I gave speedy assurance of my sincerity, and on receiving the purchase money, after handing over the Barnacles to my custody, the young urchin started off as fast as his legs, encased in huge wading boots, would allow him. His alarm was quite unnecessary, for although in a few days after I would not have given a penny for a thousand, I would willingly, on the above occasion, have paid five shillings for a single specimen, rather than have missed the opportunity of possessing such an interesting object as the Ship Barnacle.

On placing them in water one only of the creatures showed any signs of life, and by next morning they made the scentral organ of my face so highly indignant that, in order to allay its irritability, I was obliged to remove the defunct animals to the outside of the window. There they remained for several months, and were eventually transferred to the privacy of a card-board box. Although twelve months have elapsed since the last-mentioned removal took place, these creatures even now, when the lid of the case is lifted, give out a smell, so 'antient and fish-like,' that I believe not a few of 'the sweet perfumes of Arabia' would be needed in order to subdue its power.

One cluster contained thirty Lepades, and the other eighteen. The average length of each Barnacle is about three or four inches. One, however, measured nearly ten inches. The fleshy stalk is of a purplish-grey colour, semi-transparent, and perfectly smooth. The shell, which consists of five pieces, is bluish-white, while that portion from whence the cirri protrude appears of a brilliant orange, the cirri themselves being exquisitely tinted with violet, shaded off to a deep purple.

I may here mention that the above animal was by our ancestors most unaccountably supposed to be the young of the solan goose!—a bird that haunts in vast numbers the Bass Rock and Ailsa Craig. Indeed, a common belief in different parts of Scotland,and over the west of England was, that the shells grew upon certain trees, and in process of time opened of themselves; whereupon a certain animated substance contained within the shell dropped down, and according to the place where it fell perished or fructified. By falling into the water it grew to be a fowl; but by falling upon land the vital principle became extinct. The fowls which resulted from the more fortunate contingency were called Barnacle Geese in Scotland, and Brant, or Tree Geese in England. This delusion appears to have arisen from the fact of Barnacles having been found in great abundance on trunks and even branches of trees long submerged in the sea.[8]Bishop Hall thus alludes to the popular notion in his Satires:—

'His father dead! tush, no, it was not he;He finds records of his great pedigree;And tells how first his famous ancestorDid come in long since with the Conqueror.Nor hath some bribed herald first assignedHis quartered arms, and crest of gentle kind;The Scottish Barnacle, if I might choose,That of a worme, doth waxe a winged goose.'

'His meaner worksAre yet his care, and have and interest all—All, in the universal Father's love.'—Cowper.

Barnacles attached to shell of Limpet, Animal of the Limpet, The Laminated Nereis

1 COMMON BARNACLES attached to shell of Limpet2 ANIMAL OF THE LIMPET (P. vulgata) as seen from below3 THE LAMINATED NEREIS (Phyllodoce Laminosa)

Tooblige an English correspondent who requested some blocks of stone containing Pholas perforations, the writer, in company with a fellow-student, started betimes for the sea-shore, some four miles' distance. We made for a certain spot, where it was expected the object of our wishes could easily be found. Our equipment consisted merely of a hammer, a bottle, and two chisels, enclosed in a carpet-bag, the better to mask our mission from impertinent curiosity.

On reaching the shore, it soon became painfully apparent that no pieces of rock could be procured of a character at all suitable for a museum. To make matters still more irritating, a breeze arose, and with it came a furious shower of rain, which soon completely saturated our light costume. At such a time it is laughable to note how faint becomes the poetry of practical zoology—how excessively like street puddles are the fairy-grots, as the rock-pools are called; how unsightly the great, distorted anemones look, too, when viewed from beneath a large boulder,where you are crouched in the fond idea that you are thus getting shelter from the rain.

On this occasion, my friend and I, being soaked to the skin, started up from our unpleasant position, and boldly daring the rain to do its worst, proceeded to hunt after any object of interest that might by chance be lying stranded near.

After an hour's search, two objects, among many others of more or less interest, were captured, that fully repaid us for our uncomfortable 'ducking.' The first was an elegant Actinia (A. Dianthus), which seemed to be exquisitely modelled in the finest virgin wax. The second was a specimen of the Laminated Nereis (Phyllodoce Laminosa), a wonderfully beautifulworm!

Fair reader, start not nor curl that rosy lip of thine at the expression, 'beautiful,' being applied to such an humble creature, for indeed the title is a just and true one.

This Annelid is generally found coiled up and attached to the under part of stones situated near low water mark. Its general colour is emerald green, excepting along the centre of the back, which is iridescent, and reflects a brilliant blue, changing into purple and other hues, only equalled in beauty by the enamelled corslet of the brightest beetle, or the flashing tints that dance upon the plumage of the humming-bird.

The body of theP. Laminosa, like that of allotherDorsibranchiate Annelidans, is divided into a consecutive series of rings. Upon either side of each ring is situated a singular appendage, which acts as a gill or branchial organ, by the exercise of which the blood of the animal is effectually purified, and respiration adequately provided for.

When the Nereis is in a state of repose, these gills are laid flat over its back; but in a state of activity they are fully spread out, and act as 'paddles,' by aid of which the animal is enabled to glide through its native element with a graceful serpentine motion.

At the base of each paddle is situated a smaller one, consisting of a fleshy pedicle shielding a fan-like bunch of hairs, each of which tapers to a sharp point. Combined, these hairs or spines form a powerful defensive weapon, which can be extended or retracted at will; and it also serves as anoar, or propeller.

As a noteworthy instance of tenacity of life in the lower animals, it may be well to mention here that I have on various occasions, by aid of the microscope, watched for several minutes the bunch of spines, above alluded to, thrust out and retracted in a single segment cut from the body of the Nereis; and only as the object became devoid of moisture did its beautiful mechanism cease to play.

The specimen now before me is comparatively small, being only twelve inches in length, yet its body contains nearly one thousand lateral appendages, constituting,it must be admitted, a most extensive and wonderful locomotive apparatus.

This Annelid is not a suitable object for the aquarium, on account of its frequent great length, and the consequent likelihood of its getting entangled among stones and rock-work when in search of food.

If the hinder parts be cut off, as has been already hinted, they will exhibit vitality for a considerable period when placed in water, but we are told it is the anterior (?) portion of the Phyllodoce which alone possesses the power of regenerating lost segments; these will be reproduced sometimes at the rate of three or four in a week.

'These creatures,' says a learned author, 'as might be expected from their activity and erratic habits, are carnivorous; and innocent and beautiful as they look, they are furnished with weapons of destruction of a unique and most curious description. The mouth of the Nereis would seem at first to be a simple opening, quite destitute of teeth; but on further examination, this aperture is found to lead into a capacious bag, the walls of which are provided with sharp, horny plates, even more terrible than those which are occasionally to be met with in the gizzards of some of the higher animals. It is not surprising, therefore, that by many anatomists the structure in question has been described as a real gizzard, or by some as the stomach itself. A little attention to the habits of the living Annelid will, however, soon revealthe true character of the organ. No sooner does the creature wish to seize its food than this so-called gizzard is at once turned inside out, in which condition it protrudes from the mouth like a great proboscis, and the teeth, which were before concealed in the interior of the cavity, now become external, and display as formidable an assortment of rasps, files, knives, saws, hooks, or crooked fangs, as any one could wish to see. Let us suppose them, when in this condition, plunged into the body of some poor helpless victim, while at the same moment the proboscis is rapidly inverted and withdrawn; the prey thus seized is at the same instant swallowed, and at once plunged into a gulf where all struggles are unavailing, there to be bruised, and crushed, and sucked at leisure.'

There is a curious fact in connection with these Annelids which is too interesting to be omitted here. I allude to the wonderful manner in which their young are produced by a process that may be called 'sprouting.'

This invariably takes place in the segment immediately preceding the terminal one. When a new animal is about to be formed, the reproductive segment swells, and after a certain time the infant worm is seen growing from the tail of its parent. When sufficiently developed, the offspring detaches itself, and starts life on its own account. Sometimes before the elder born Annelid is fully formed, themysterious segment produces a second offspring, and, according to Professor Milne Edwards, as many as six young ones may be generated in succession from the same posterior segment, all of which will for some time continue attached to the parent worm.

Atthe lowest ebb of spring-tide may often be seen protruding above the surface of the beach an object that at a little distance might be mistaken for the twig of a tree, or a decayed and blackened reed. A close examination discloses it to be a smooth, tough tube, apparently composed of dark leather or old gutta-percha, affixed at its lower extremity to some rock or other solid substance.

The pretty Annelid occupying this dark cylinder is the Fan-Amphitrite (A. ventilabrum). Unlike the Terrebella, this animal may really be captured without much difficulty. The first time I made the experiment it was successful. By carefully digging down with chisel, or digits, to the base of the tube, which may be reached in the course of a few minutes, the entire structure, with its living occupant, may be transferred to your extemporaneous tank.

I have an Amphitrite in my aquarium at the present time displaying its richly-tinted tentacula to the sun, which lights them up with unusual beauty.

As the 'case' of this animal is flexible, and as its owner will only thrive in an upright position, the reader will easily conceive that to afford the Annelid suitable accommodation in the aquarium is not a very easy task. What other naturalists do I cannot tell; but the following is the plan I adopt for the creature's comfort and my own gratification:—

Having procured a small cylinder of glass (or gutta-percha), close up one end, and drop in the Amphitrite, taking care to first tie the lower portion of its sheath with a piece of thread or silk. It is very pretty to see the plume of the Annelid spreading completely over and covering the extremity of the tube, giving the idea in the one instance that the animal was mysteriously gifted with the power of exuding gutta-percha instead of its usual mucus.

The Annelid may be made to recline against the sides of the vase, or be propped up on any chosen spot by aid of a small cairn of pebbles, and thus form a very curious feature in the aquarium.

To test a fact, relative to the power which the Amphitrite is said to possess, in common with other tubiculous Annelids, of renewing certain portions of its body after sustaining injury, I snipped off the principal portions of its branchiæ, and found that, after the lapse of a few months, my specimen renewed its mutilated organs.

'Travelling is not good for us; we travel so seldom. How much more dignifiedleisurehath a Mussel glued to his impassable rocky limit two inchessquare! He hears the tide roll over him, backwards and forwards,twice a day (as the Salisbury coach goes and returns in eight and fortyhours), but knows better than to take an outside place on the top on't.He is the owl of the sea, Minerva's fish, thefish of wisdom.'C. LambtoB. Barton.

Mussels

1 COMMON MUSSEL (Mytilus edulis)a The footb The byssusc c Muscles which regulate the action of the foot2 THE MUSSEL CLOSED3 THE BERÖE (Cydippe pileus)4 THE FAN AMPHITRITE (A. ventilabrum)

Inhis celebrated journey to the western islands of Scotland, Dr. Johnson tells us that when at Ulinish, hearing of a cavern by the sea-side remarkable for powerful reverberations of sound, he determined to pay a visit to the spot. After dinner, having procured the services of some boatmen, the doctor, in company with Bozzy, started off on his trip, which, on the whole, appears to have been a pleasant one. There was, however, noechoto be heard; but to make up for this disappointment, Mr. Boswell went angling, and caught a wee 'cuddy,' (a fish about the size of a gudgeon), while the doctor was gratified by the sight of some sea-weed growing upon stones, and above all, at witnessing for the first timeMussels in their natural state.

The impression made by this candid acknowledgment upon our minds is one of wonder, that a man like Johnson could have reached his advanced years without having seen so common a sight. But it is possible that even in our day, with its unprecedentedfacilities for cheap travelling for the most inland inhabitants, there may be many persons to whom the sight of a Mussel fixed to a boulder by its self-constructed cable, would be as great a novelty as it was to the eloquent author of Rasselas.

It is, however, one of the commonest appearances which meet the eye of those in the habit of visiting the sea-shore. At certain localities myriads of Mussels may be noticed attached to the surface of the rocks. So thickly are these sometimes covered over, that the blade of a knife cannot be inserted at any part without touching one or more of the esculent bivalves that are to form the subject of this chapter.

The Mussel anchors itself by means of the Byssus; or, as it is commonly termed, the 'beard.' This appendage is composed of various slender threads which are attached to any object within reach, whether such be the shell of a neighbouring Mussel, a small stone, or huge boulder. The members of each colony are thereby bound together, it may be figuratively said, by the silken cords of friendship, and mayhap of love. TheMytilievidently believe that 'there's no place like home.' Although gifted with a power of moving about at will, they never attempt to exercise this when living together in a family circle, but pass through life's stages upon the spot where they were born. Certainly,if there be such a sight as a truly happy and contented family in the marine animal kingdom, it is to be found exemplified in these bearded molluscs.

As hinted, they live shoulder to shoulder, back to back, and otherwise mutually support each other. They need not look about for a single meal, but have merely to allow themselves to be fed by the waves, which yield them a constant supply of fresh and wholesome food. Their sole duty in this respect is limited to the selection of objects suitable to their palate. Their 'at homes' being so frequent, theMytilican boast of a large circle of acquaintances. The Periwinkle, and his friend Silver Willie, often make a morning call, take pot luck, as it is termed, and then politely retire.Mr. Carcinus Mænasand his poor and dirty relation,Maia Squinado, perchance look in of an evening.Solaster Papposa, or occasionally the lanky-leggedUraster Rubens, and other 'stars' of the marine world, crawl in at unseasonable hours in their usual lazy style, and are generally rewarded by finding the doors (valves) shut against them. This 'cut direct' does not appear to be at all annoying; or if so, the Star-fishes are too cunning to show it, for they quietly saunter away as if they never had the slightest wish to put their feet within their neighbour's dwelling.

There is a 'black sheep,' as Sir Pertinax Mac Sycophant would say, who intrudes himself intoMussel society, and plays sad havoc among its members. This crawling rascal is the wolf of all Musseldom flocks. Young and old alike experience the blighting effects of his villanous propensities. The name of this obnoxious personage isPurpura Lapillus(Common Whelk). What, the reader will ask in surprise, a univalve prey upon a bivalve? Is that possible? It is, unfortunately, too true.

If we take a Mussel in our hand we shall find it perfectly impossible to force its valves asunder, without the aid of a strong knife or other instrument; yet the Common Whelk, fleshy and insignificant creature though it be, will consume the animal within, and make the valves fly open in a brief space of time, by means of its soft tongue. But leaving such general remarks, let us suppose we are standing before a boulder covered with these mussels. Numbers of gaping shells may be at intervals perceived still attached to the rock, but with the interior of each valve so empty and smooth, that we could scarce believe they had ever embraced a living occupant. On taking up one of the valves and closely examining it, do you observe nothing peculiar about it now? 'No.' Take up the other then, and submit it to a similar inspection. Well, what do you see now? 'Nothing,' you still reply, 'unless it be a peculiar little hole about the size of a pin's head, which surely is of no importance.' That little hole was ofvitalimportance to the poor mollusc, forthrough that aperture the life and substance of the Mytilus was drawn by the voracious Purpura.

But the poor Mussel is exposed to the attacks of other enemies—aquatic birds, as sea-gulls and ducks, eagles, vultures. Even water-rats and monkeys may also be included in the list.

It is amusing to see a gull, by no means a foolish bird, standing patiently before a Limpet, for example. The animal, unsuspicious of the presence of an enemy, raises his canopy with the view of relaxing his overstrained muscles, and is instantly toppled over by the intruding beak of the bird. If unsuccessful in his first attempt, the gull is well aware it would be useless to try a second time at that tide.

But if a Mussel be the object of attack, it is wrenched from its seat, raised to a certain height, and then allowed to drop upon a stone with the view of breaking the shell. In one locality called Mussel Bay, Mr. Barrow says he disturbed some thousands of birds, and found so many thousands of shell-fish scattered over the surface of a heap of shells, that, for aught he knew, would have filled as many thousand waggons.

This habit of the feathered tribe was, by the way, well known to the ancients, and I may be pardoned relieving my pages by a quotation on the subject from the 'Shepherd's Calender' of Spenser, whose exquisite descriptions of natural history are as marvellous as his allegorical poem. The author of the'Fairy Queen' thus humorously reads a lesson to an ambitious man,—

"He is a shepherd in gree,But hath been long ypent,One day he sat upon a hill,As now thou wouldst mee;But I am taught by Algrinds ill,To love the lowe degree.For sitting so, with barred scalpe,An eagle soared hye,That weening his white head was chalke,A shell-fish down let flye!She weened the shell-fish to have broke,But therewith bruised his brayne,So now astoined with the stroke,Hee lyes in lingering payne!"

It seems remarkable that the 'illustrious French naturalist,' Reaumur, should have been the first, if not to discover, at least to publish, any description of the manner in which the Mussel spins its silken cable. Yet one hour's experience in a tea-cup or tumbler will exhibit most of the features in this interesting process.

That Reaumur's narrative, although usually copied by most writers of the present day, is not strictly correct, and, moreover, that the foot of the mussel isnot'useless as an instrument of progression' (as generally asserted), may be easily proved to the satisfaction of the student by adopting some such simple experiment as that which I am now about to describe:—

Being at the sea-side on a fine summer afternoon, I procured three specimens (I might have had as many hundreds if disposed) of the Mytilus. On myreturn home I placed them in a common tumbler, and waited patiently to see the result. My object was, if possible, to witness the manner in which this animal grows its beard.

In less than five minutes an industrious little fellow, whom we will call No. 1, gently opened his shell, and immediately protruded his fleshy foot until it reached a length of nearly two inches. So far as I could determine, the design of the Mussel was to discover, in the first place, what kind of a lodging he occupied; whether or not he had any companions; and also, to know if these or any other objects could be found worthy of hisattachment.

Sometimes the foot would be protruded under the shell, then in a contrary direction. Or by an exertion of the strong muscular power which that organ possesses, the entire shell would be lifted off the ground and urged forward to a considerable distance. Of course he soon come in contact with a neighbour Mussel, whom we may term No. 2, but as the latter was not anchored by any byssus, he was speedily pushed on, and on, until No. 3 was met, and the latter, in his turn, made to take up a new position.

Being tired of wandering about, No. 1 then extended his foot along the base of the vase to a certain point, and there let it rest for a few seconds. When again withdrawn, to my great delight, I saw the first thread of a new byssus had been constructed.

As my principal object was to become acquainted with the mode of formation of the beard, I did not feel satisfied with merely watching the movements of the animal from above. After a brief interval another thread was spun. I bore in mind the words of Reaumur, who says, 'The Mussel never spins more than four or five threads in the twenty-four hours.' Aware that no time must be lost, though still afraid to disturb the mollusc lest it might suspend its labours, I instantly detached my specimen, and again turned its shell round so as to bring the opening of the valves against the face of the glass. The creature did not seem at all offended at his handiwork having been destroyed, but still obstinately refused to let me see the working of its foot. Again was the shell rolled over, and again did I replace it in its former position. This time, in order to keep it from being shifted, a stone was deposited upon the valve. Nothing daunted, the animal gradually separated the valves of its shell, and at the same time advanced and elevated its foot to the exact position that I had so long desired.

The spinner, when at its full length, was pressed firmly upon the flat surface of the glass, and there allowed to remain for a while. Suddenly, at nearlyhalf an inch distance from its extreme end(or point), a little mouth was seen to form, about the size of a large pin's head, from which there issued a milk-white fluid, that gradually hardened and becamefixed to the glass. This object being light in colour, had a pretty effect when contrasted with the rich brown tint of the spinner. Shortly afterwards the foot rolled over and withdrew into the shell, leaving behind it the silken thread which had just been spun. The 'little mouth,' above described, was, if I may so term it, the mould in which the end of the thread was cast.

In the course of two hours a bundle of byssus threads, sixteen in number, were produced by this industrious little labourer.

Having thus seen that the foot is useful to the Mussel as an instrument of progressionbeforethe beard is formed, let me now endeavour to show that it is, at times, of equal service for the same object,after, and when the mollusc is anchored thereby to any particular spot.

When we remember that this anchorage is formed of a harp-like set of strings, amounting to ten or evena hundredin number, it does seem an almost incredible fact that the Mytilus is enabled to change its station, even when living in single blessedness.

To see a Mussel 'flit,' is a sight one may often watch and wait for without success. On the other hand, when least expected, the self-willed mollusc may commence operations. When about to take up a new home, the animal shaves off its beard entirely, or in more scientific language, 'rejects its byssus' altogether. In order to excite the locomotive instinctsof my specimens, I used to cut all the threads of their cable except one. The animal being suspended, of course its whole weight was then thrown upon a single fibre. Such a state of insecurity was by no means agreeable, and I generally found in the course of a few hours that fresh threads were rapidly thrown out, and an entirely new byssus formed; the old one, which was broken off at the root, being left behind as useless.

Another singular peculiarity of the Mussel which came under my observation has not been, so far as I am aware, noticed by previous naturalists. I allude to the power which the animal possesses of lengthening out the root or stem of the beard, apparently to an unlimited extent. This power appears to be seldom exercised, for although I have had hundreds of specimens of the Mytili, in only one instance have I witnessed the phenomenon in question.

A large specimen of this bivalve, procured accidentally from a fishwife in the street, was dropped into the aquarium, and placed close against the surface of the glass. The animal seemed highly delighted with its change of situation, for in a few moments the valves were opened, and a long draught of water taken in to bathe its branchiæ, and furnish a hearty meal. Having satisfied its appetite, the next process, of course, was to find out what kind of a home he had been introduced into. The foot, a noble specimen, was soon protruded, and one after theother, in rapid succession, various threads were formed. By next morning the animal, advancing by a series of easy stages, had reached the surface of the water, which was exactly five inches deep. I knew it would not remain long in this position, and was anxious to discover what plan would next be adopted. Several courses were open to him. For instance, like a marine Captain Cook, he might circumnavigate his littleGlobe,—or he might let go his cable and drop plump to the bottom,—or he could follow the route I had often seen taken by his relations, viz., to journey back to the place from whence he started. It pleased him, however, to strike out into a new path,—to devise a method of his own. While located near the top of the tank, he threw out exactly ninety-eight threads, not certainly for security, but merely, it would appear, for pleasure.

Then slowly but surely, day by day, he lengthened out the stem of his byssus tree, until it reached the extreme length of nearly five inches. To what further degree it would have been extended, had the mollusc not reached the base of the tank, it is impossible to conjecture.

No sooner did the shell touch terra firma, than the cable which had taken so long to spin was immediately broken off. I have succeeded in keeping the same animal by me for the last twelve months, but have seen no attempt at a renewal of the operation, in the progress of which I had taken so lively an interest.I may add that this Mussel taught me another lesson; it was this: in my early studies regarding the habits of the Mytilus, I had adopted a certain theory of the manner in which the beard was formed; and having watched so long, and witnessed the process so repeatedly, I thought myself justified in forming certain conclusions. My belief was that the creature could not form more than one thread at a time,without withdrawing its foot into the shell, as I believed, in order to procure a fresh supply of material. That this notion was erroneous, this animal proved to my entire satisfaction. Not only may one, but two, three, four, and even six threads be attached to any selected object, the point of the foot being passed from one position to another, without the organ being withdrawn into the valves until the whole of the threads are formed. How many more the Mussel is capable of producing at one 'stretch,' I have no means of knowing, but six is the largest number that any of my specimens in such case have ever fabricated.

The general idea seems to be that the Mussel works in the same manner as the spider, who emits a drop of liquid against some foreign substance, which, being allowed to harden somewhat, is then drawn out as the spider recedes. This notion, I may state, is quite erroneous. When the sucker of which we have spoken is formed,the thread is completed. It is true that the foot as it retires into theshell generally glides down the newly-constructed filament, but this is not of necessity, nor does such circumstance invariably occur. Indeed, while busily engaged in attaching a disc to the glass, the muscles of the foot will contract, and thus throw open the folds of the groove, situated in the middle of that organ; when thus exposed, the byssus thread may be seen in the furrow, stretched like the string of a harp or dulcimer.

While the end of the thread is being attached to a certain spot, a conspicuous muscular action is perceived going on in the foot, which alternately swells and contracts, as if something were being pumped up through the byssal channel, until it reached a certain point. There being dilated and spread out in successive layers, it assumes a trumpet-like disc, which is firmly fixed to the foreign object. Indeed, I am by no means certain that the thread is not, when first produced, exactly like a trumpet in shape. It also conveys the idea of being blown out in a similar manner to a piece of bottle glass. After being exposed to the air for some little time, the hollowness of the thread is not so apparent as when it is newly fabricated.

The mucous fluid, from which the fibres are formed, is secreted in a gland situated at the base of the foot, whence it is apparently expelled at the will of the animal into the furrow already referred to, and is there spun into threads. The toughness of thesefilaments, considering that each is finer than the thinnest strand of silk, is remarkable. Their strength, however, may be easily accounted for, when we know that each is composed in reality of innumerable delicate threads, bound together by a subtle gelatinous fluid. This phenomenon may be made out quite distinctly with a common hand lens, if the following simple experiment be adopted: Make a Mussel construct its thread in such a way that the disc of each is planted on the face of the glass. Then place the fine point of a common needle upon the outer edge of a chosen disc or sucker, and gently draw the former away to a little distance, and you will find that by so doing the stretched string becomespeeled. Continue this process carefully, and before the thread gives way you will have divided it into a dozen parts at least, all of which are visible to the naked eye, but clearer when the hand lens is used, and still more distinctly and beautifully defined, of course, if the microscope be brought into play.

The foot of the Mussel appears to be firmly strapped on, as it were, to certain transverse muscles, by a contraction of which the animal closes its shell with surprising force. This strap, composed of a powerful tendon which passes under the adductor muscles, is attached at either end to the base of the foot. Thus we account for the remarkable strength which is evidently seated in the foot, and makes it of so much importance to the animal. At firstsight nothing appears more easy than to pluck out this organ by the roots, but an attempt will prove the experiment to be more difficult than many persons suppose.

The colour of the foot varies considerably in different specimens, even of the same species. Some, for instance, are of a chestnut brown; others of a kind of mauve or purple, covered with a peach-like bloom during life; others, again, are of a deep-toned umber, while not a few are pearly white, and streaked sometimes with pink like a tulip.

The peculiarity of the Mussel to attach itself to foreign substances has been taken advantage of for the benefit of man, and a curious instance is exhibited at Bideford in Devonshire, at which town there is a bridge of twenty-four arches, stretching across the Torridge river near its junction with the Taw. 'At this bridge the tide flows so rapidly that it cannot be kept in repair by mortar. The corporation, therefore, keep boats in employ to bring mussels to it, and the interstices of the bridge are filled by hand with these mussels. It is supported from being driven away entirely by the strong threads these mussels fix to the stonework.'

Like most other writers who quote this strange account, I have not had ocular proof of its accuracy.[9]That it is quite probable I can readily believe, as apretty experiment will partly prove it to any spirited aquarian. Following out the above idea of the bridge at Bideford, I managed to build an exceedingly pretty centre piece for my tank.

Having no ready means of making a rock arch, I collected such pieces of rock, stones, &c., with weeds attached, as I thought would answer my purpose, and then proceeded to fabricate the object of my wishes in the following simple way: First were laid two stones parallel to each other at three or four inches apart. Upon these I placed a large piece of rock in a transverse direction. Between the interstices a number of small mussels were then inserted. When fully satisfied that the bivalves had moored themselves, I gradually piled one piece of rock upon another until the structure reached the desired height, each piece being bound to its neighbour by means of the byssus threads of the Mytili.

Before each block of stone that formed the foundations of the arch was placed a splendid frond of Lettuce Ulva, tied by a strand of silk to a white pebble. These verdant fronds, so smooth in texture and so gracefully convoluted, rising up from the baseof the tank and reaching to its brim,—mingling, too, with the various tufts of corallines and other sea-weeds that jutted from each crevice, were very pretty to look at. When disturbed by the movements of the fishes passing in and out, the gracefulness and beauty of the sea-weed was doubly increased.

In making observations upon any bivalve, such as the Mussel, it is extremely puzzling to know what is going oninsidethe shell. Yet it is almost necessary to acquire this knowledge by means not always apparent, in order to satisfy one's mind relative to certain appearances, which we perceive going on externally. We have to form our judgment of things we do not see from those that are apparent—at all times a difficult task. But not often so tantalizing as in the case of an insignificant creature like the Mussel, who lives, moves, and works constantly before our eyes. I may add that it was not enough for me that I saw the spinning process frequently. It all seemed tolerably clear to my mind, but still I did not feel thoroughly satisfied. My desire was to peep into the shell, and find out where the last spun thread was situated; or, in other words, from what part of the trunk the new branch sprung. On examining various specimens of the byssus, this point was by no means apparent. Various means I adopted failed to secure me the requisite knowledge. At length I hit upon a plan, which, after no long time, I found opportunity to put in practice. My largestMussel lifted up its testaceous canopy, put aside the fringed and fleshy veil that surrounded its edge, protruded its spinner to make sure the ground was secure, and then withdrew it again into the shell as usual. After the lapse of a second, the foot reappeared and was stretched out to an unusual length. No sooner was the end of the thread formed on the glass than immediately I firmly pressed the valves together, and held them in this position until I had gradually worked the Mussel up out of the vase, when I bound them close together by means of a piece of cord. I need not describe my manœuvres further; suffice it to say that the thread nearest to the base of the groove was found to be the one that was spun last. This, in my opinion, is invariably the case.

I may mention that the above experiment also proved to my mind that the foot must be a most important vital organ of the Mytilus. At times, on placing an open Mussel in my tank as food for crabs or other animals, I have noted that if every other part were eaten, and the foot allowed to remain attached to the muscles of the bivalve, that member would after a lapse of several days show signs of—I do not say life—but sensation and retractile power.

But when the foot is cut and otherwise injured, the animal dies quickly. In the experiment mentioned the valves were not kept closed for more than half an hour; yet when they were opened, vitalityhad evidently ceased within. This was the more singular when we remember that the Mytili will live for many days out of the water; the shells, of course, during the whole period being firmly closed.

The Mussel, as already hinted, is very tenacious of life. I have kept specimens by accident for several days in the pocket of my coat, but found them quite well and lively when placed in sea-water.

In general the sure sign of their not being in a healthy condition is when the shell opens; for, while the animal retains any sense whatever, it exercises a strict and judicious 'closeness.'

I have found, however, on several occasions, that the shell being contracted is not always a valid proof of its owner's convalescence, for when placed in water the Mussel would float for several days upon the surface like a cork, although it was near death's door.

This phenomenon must be caused, I should suppose, by some sudden fright compelling the mollusc to close its shell with such rapidity as to prevent a proper supply of water being taken in. Having only air to exist upon, the animal then lingers on until its branchiæ become dried up, and all moisture exhausted. In this state the Mussel opens its shell with a deep bursting sigh, and sinks to the bottom—dead.

Being at the sea-side one fine summer day, I heard a little Scotch girl cry out to her brother who was about to swallow entire, a fine specimen of theMytilus edulis, 'Eh, Willie dear, dinna ye eat that. Dinna eat thebeardor ye'll dee!' Many years ago I remember a remark to the same purport as the above being made by a poor child to its playmate, in the neighbourhood of Gravesend.

I little thought at that time that the Mussel was so interesting a shell-fish, or that I years after should spend many an anxious hour studying the formation and nature of its despised beard.

I need hardly state that the idea of the beard being poisonous is a vulgar error. In general the fish may be eaten entire with impunity.

Cases have occurred where persons have been taken ill after eating it, but this result has been satisfactorily explained to have been caused by the Mussels being procured from places such as Leith Docks, where their food consisted chiefly of unwholesome and putrescent matters.

This mollusc is not used as food to any very great extent by the poorer classes. It is employed very extensively, however, by the fishermen as bait along all parts of the British coast. But in France it is much esteemed both by rich and poor. The trade in them is successfully cultivated, and affords a means of support to hundreds of industrious and deserving men.

From the learned author of the "Rambles of a Naturalist" we learn that at the village of Esnandes, on the coast of France, the Mussel trade, commencedabout eight hundred years ago, has assumed a gigantic extent. Both here and at the neighbouring villages of Charron, Marsilly, Mussels are bred in an ingenious and systematic manner. At the level of the lowest tide short piles or stakes are driven into the mud, in a series of rows about a yard apart. This palisade is then roughly fenced in with long branches. On this structure the Mussel spawn is deposited, and it is found that the molluscs thus produced in the open sea are much finer than those which are bred nearer the shore.

These artificial Mussel beds are termed 'bouchots.' The fishermen who engage in this branch of industry are known as 'boucholeurs.'

'The little Mussels,' continues M. Quatrefage, 'that appear in the spring are known asseeds. They are scarcely larger than lentils, till towards the end of May, but at this time they rapidly increase, and in July they attain the size of a haricot bean. They then take the name ofrenouvelains, and are fit for transplanting. For this purpose they are detached from thosebouchots, which are situated at the lowest tide mark, and are then introduced into the pockets or bags made of old nets, which are placed upon the fences that are not quite so far advanced into the sea. The young Mussels spread themselves all round the pockets, fixing themselves by means of those filaments which naturalists designate by the name of byssus. In proportion as they grow and become crowded togetherwithin the pockets, they are cleared out and distributed over other poles lying somewhat nearer to the shore, whilst the full-grown Mussels which are fit for sale are planted on thebouchotsnearest the shore. It is from this part of the Mussel bed that the fishermen reap their harvest, and every day enormous quantities of freshly gathered Mussels are transported in carts or on the backs of horses to La Rochelle and other places, from whence they are sent as far as Tours, Limoges, and Bordeaux.... The following data, which were collected by M. D. Orbigny more than twenty years ago, will show how important this branch of industry must be to the district in which it is cultivated. In 1834 the three communes of Esnandes, Charron, and Marsilly, representing a population of 3000 souls, possessed 340bouchots, the original cost of which was valued by M. D. Orbigny at 696,660 francs; the annual expenses of maintaining them amounted to 386,240 francs, including the interest of the capital employed, and the cost of labour, which, however, is spared to the proprietor who works on his own account. The nett revenue is estimated at 364 francs for eachbouchot, or 123,760 francs for the three communes. Finally, the expense of the carts, horses, and boats, employed in transporting the Mussels, then amounted annually to 510,000 francs; but these numbers are far from representing the expenses or profits at the present day. At the time M. D. Orbigny lived at Esnandes,thebouchotswere only arranged in four rows; now however, there areno less than seven rows, and some of them measure more than 1000 yards from the base to the summit. The whole of thesebouchots, which were at first limited to the immediate neighbourhood of the three villages, of which I have already spoken, extend at the present day uninterruptedly from Marsilly far beyond Charron, andform a gigantic stockade for two miles and a half in breadth, and six miles in length.'

A curious circumstance connected with the Mytilus remains to be described. Let the reader, who may be so fortunate as to possess a good microscope, cut away a portion of the fleshy part of the Mussel, then place it in a watch glass, and examine it through that 'portal to things invisible,' and, unless I am much mistaken, he will own the sight to be supremely wonderful. Some water being deposited in the glass the fleshy object will be seen to swim about in a most singular and mysterious manner, while a close inspection shows every portion of it to be in active motion.

This motive power is caused by countless cilia, the rapid vibration of which creates constant currents. This action preserves the health of the poor mollusc by ærating the water which passes over his respiratory organs.

That some such wonderful contrivance is adopted, for conveying food within the valves, too, is evident,when we consider that the Mussel is always affixed to some foreign substance, that it cannot hunt after prey, and therefore can subsist only upon whatever nutritious particles may be contained in the element in which it lives. These consist of minute animalculæ, principally crustacea, which are drawn within the shell by powerful currents.

I have often watched this phenomenon through a hand lens, and have seen the young shrimps and skip-jacks, for instance, notwithstanding the nimbleness of their movements, irresistibly drawn into the gulf of destruction. Even tolerably sized specimens that were seated in fancied security upon a valve of the Mussel, have suddenly been drawn in, out of sight. As an instance of the power of these currents, I may state that the water in a small aquarium is often seen to be affected by the respiratory action of a single bivalve. The same thing has even been apparent to the writer, while watching the movements of a colony of Barnacles attached to a Limpet, the most distant part of the fluid being gradually drawn near, in obedience to the beck of these delicate and graceful little creatures.

'Whether progressing on the solid surface, or moving through the water, ortunneling the sand, advancing or retreating in its tube, the Annelid performsmuscular feats distinguished at once for their complexity and harmony. Ingrace of form the little worm excels the serpent. In regularity of march, thethousand-footed Nereid outrivals the Centipede. The leaf-armed Phyllodoce swimswith greater beauty of mechanism than the fish; and the vulgar earthworm shamesthe mole in the exactitude and skill of its subterranean operations. Why, then,should the "humble worm" have remained so long without a historian? Is thecare, the wisdom, the love, the paternal solicitude of the Almighty not legiblein the surpassing organism, the ingenious architectures, the individual andsocial habits, the adaptation of structure to the physical conditions ofexistence of these "degraded beings?" Do not their habitations display Hiscare, their instincts His wisdom, theirmerrimentHis love, their vastspecific diversities His solicitous and inscrutable Providence.'—Dr. Williams.

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