By the deep sea

The breathing organs (branchiæ) of these tube-masons are external, and form a very beautiful object when the worm lies on the threshold of his house and pushes this apparatus out, that his blood may benefit from the abundant oxygen of the ever-moving waters. At first the branchial plume issues very cautiously and with slight pauses and withdrawals; but finding all safe the Sabella at length gets it quite out and expands it to its glorious fulness, delicate in structure, splendid in colour as the light is variously reflected from the finely-toothed threads.

We must use the lens if we are to get an idea of the structure of this beautiful crown. By its aid we find there are a great number of filaments, each one fringed with finer processes on each side. Fine as these are, they are all hollow, and through them the blood constantly flows, to be brought in contact with, and to absorb the oxygen of the sea-water, which can pass through the microscopic meshes of their walls through which, however, the free cells of the blood cannot pass. In some species these gills are arranged not in circular form but spirally round a central shaft.

Among the numerous species of Sabella to be found on our shores, there is one that is not inaptly termed the Silkworm Sabella (S. bombyx), and indeed, being a real worm it has more claim to the title than has the caterpillar that is called the Silkworm. This silk-producing Sabella, however, could scarcely be pressed into the service of man, though one could fancy an imaginative writer employing this spinner to make gossamer vestments for sea-fairies, for the material produced is of just the texture a fairy would desire. Not long ago, I introduced to one of my aquarium vases a flat stone that supported a sea-anemone, which I was loth to disturb, and would rather he moved off on his own account. In doing this, one never knows what one may be introducing in addition to the specimen desired, unless one takes the precaution of scraping or scrubbing the stone. A week or two later, I was surprised one morning to find several threads—so clear as to be scarcely visible—running up from this stone at the bottom to a point about four inches up the glass. Next day there was more of it, and so on from day to day the quantity increased, and the older portion became more visible than before, for its extreme transparency passed away, and it became dusty-looking—in fact, cobwebby. By this time it was clear that what had at first looked like purposeless threads and filaments were really part of a quite voluminous tube.

One of the most plentiful of these tube-making worms is the Spirorbis, which is to be found everywhere on stones, rocks, and weeds in the littoral zone. More especially shall we be struck by its numbers when we observe it thickly studding the fronds of the Toothed Wrack (Fucus serratus), for the dark olive hue of the Wrack throws up the dead-white Spirorbis tubes very strongly indeed. These tubes and the animals that form them are very like Serpulæ, but the tube instead of being more or less straight, or merely twisted, is coiled in a flat spiral, like the shell of the fresh-water Trumpet snail (Planorbis). Normally these are very flat at the base, and regularly formed, but where (as in specimens before me) they are densely crowded on the Wrack, there is not sufficient room for this regular growth when they get large, and the outer turns of the spiral are twisted aside and greatly distorted. The worm is very like a Serpula, closing its shell with a similar stopper, but the branchial plumes are not nearly so extensive, these rosy appendages being but six in number in Spirorbis.

It is impossible to do much work upon the shore before coming upon some specimens of another species of tube-maker, though of a less artistic character. The probability is that you will turn over a flat stone that is partly imbedded in the sand, and under it will find a furrow with an active worm wriggling through it. On glancing at the stone the explorer finds that he has ruined a habitation by forcibly tearing off the roof which had been cemented to the stone for greater security, and continued for some distance beyond the stone on either side. The tube, as a fact, is of great length, so that the worm, which is not more than six inches long, may have ample room for exercise without going into the dangerous glare of daylight, to be seen by some ravenous fish. This species is commonly known as the Sand-worm (Arenicola piscatorum). In some districts it is the “Lug.” It is popularly thought to be a favourite bait with fishermen, and it is so described in all the books; but in the part of Cornwall where this book is being written the fishermen do not set great value upon it, though they highly appreciate the Wilfry or Woolfry (Nereis pelagica).

The Lug does not produce a very favourable impression when you have turned him out of his burrow, for his very dark greenish hue looks black at a little distance, and his branchial tufts give him a ragged appearance. The fore part of his body is much swollen, but runs off to a point where the proboscis is situated. The branchiæ are attached to about a dozen of the middle rings only, in branching tufts that change from green to crimson. It is a rapid burrower, opening a way through the sand with its proboscis, widening it with the thicker part of its length just beyond, and exuding a mucous cement that agglutinates the grains of sand and leaves the passage open for further use. Its body is cylindrical throughout.

In similar situations we shall find a vertical shaft of sand protruding from the shore, with a kind of halo of fine branching sandy tubes around the mouth. The whole structure will consist either of grains of sand or fragments of shell cemented together on a silky lining. Its mouth is about an inch above the level of the sands, but the tube, if carefully dug out, will be found to extend to a foot or more. This is the home of the Sand Mason or Shell-binder (Terebella littoralis); and now that the tide is out the master of the house will probably be lying, like Truth, at the bottom of his well-like structure, and ready to bolt still deeper in the sand if necessary. He is about four inches long, and the most distinguishing feature is a regular mop of pink tentacles around his—I had almost said head, but he has no head, so we will substitute the more correct expression “anterior segment.” The gills are much branched, and there is a bright red stripe along the under surface. There are several allied species; one known as the Potter (T. figulus) from its choice of mud or clay as the material for its tube.

There is a remarkable worm called Cirratulus that lives in stones. Some say he bores the stone, but of that I am very doubtful; but there is no question that he lives in the perforation. Gosse says “under stones,” and I have no doubt Gosse is right; it is sometimes taken under stones, I dare say, for it leaves its burrow occasionally and sees the outside world. A living specimen now before me is in that free condition, having quitted its stone yesterday, Boxing Day, 1895, and not yet settled down again. He is evidently an up-to-date worm, and goes out on Bank Holidays! He is about four inches long, though from his restless wriggling and obvious objection to assuming a straight form, it is not easy to measure him accurately. His body proper is of a fine cinnabar colour, and appears to be hung loosely in a clear outer skin, which is very roomy in the fore half, sufficiently so to allow the contained body to curl and twist and double upon itself without affecting the envelope. A series of sausage-shaped expansions of this envelope constantly travel from the rear, forwards, and are caused by water that has passed through the creature’s gills and is now making its way out along the outer envelope. Cirratulus has a head, a rather poor one, and a mouth, but it is not easy to find either, for the segments near the head produce an enormous mop of tentacular processes, many of them five inches in length, which completely hides the head and mouth. These are of the same bright red as the body, and when they are extended in all directions, and the creature in a good light is shown to those ignorant of Annelid-beauty as a worm, it causes a considerable shock to their notions of worm-repulsiveness. This shock is not abated when the light plays on the bristles and a ripple of silvery flashes runs along them. In the dark a gentle touch will cause the entire creature to flash with a bluish electric light, which runs also along every one of the hundreds of finely attenuated filaments from the head-region.

There is a group of these lowly creatures that are really magnificent. They build no tubes, neither do they sink definite tunnels, but they shun the light and lurk under stones, in the chinks of rocks, and round about the roots of seaweeds. Such are the Leaf-worms (Nereis), of which several are of great length. They have more or less linear bodies, of equal thickness for the greater part of their length, and consisting of a great number of joints. The head is conical, and adorned with several antennæ. They are carnivorous creatures, and have the proboscis armed with a pair of jaws well toothed. The well-developed feet protrude from the side, and bear gill-warts at their tips, and jointed bristles. One of the most plentiful and striking of these is the Wilfry (Nereis pelagica), previously alluded to, a killing bait for sea-fishing, for no fish can resist its glowing play of iridescence. The colour is a pale fleshy-fawn, but with a succession of metallic gleams shooting over it. It is six or eight inches long, and exceedingly active in its movements. Its favourite habitat is the fœtid black muddy sand, rich in organic matter, that collects in hollows between the rocks, or in the mud of brackish creeks.

If you desire a real good day’s fishing, spend half of the day before in grubbing for this worm, with bare legs in the rich mud of such a creek; a better plan is to pay somebody a few pence per dozen to get them for you, and save yourself much discomfort.

Another species is the Pearly Nereis (Nephthys margaritacea), similar to the Wilfry, but much smaller and running off to a very slender point behind. The warm fawn colour of the upper surface exhibits lively silvery iridescence, very suggestive of mother o’ pearl. The large proboscis is cleft in two and adorned with a fringe of greenish processes. The large feet carry each a leaf-like expansion in front of each branch, and tufts of bristles. It occurs chiefly in the sand near low-water.

The Rainbow Leaf-worm (Phyllodoce lamelligera) is one of the most glorious of this group of worms, for each of its three or four hundred segments bears a couple of expansive leaf-like plates, which are the breathing organs. These are of a vivid green colour, and on the back of the body proper this hue changes to blue-green shot with purple and olive gleams. Its head is rounded, and is distinguished by the tentacles about it. This species attains a length of over twenty inches, but there is, among several others, a small intensely-green form (Phyllodoce viridis) about two inches long, to be found among the roots of weeds on low rocks. As this is very slender and of thin texture, it can be well examined under the one-inch power of the microscope, when the rowing action of the gill-leaves, and the extrusion and withdrawal of the bundles of crystal bristles will be seen.

Another family of these tubeless worms is represented in the Sanguine Eunice (Eunice sanguinea), of which specimens may be found a couple of feet in length, and of considerable thickness. It is green in colour, but the gill-plates are of a glowing blood-red. One edge of these plates is cut up after the fashion of a comb; and its head is ornamented by fine antennæ. M. Quatrefages has left a graphic description of this worm under the microscope, and as that account has not been greatly hackneyed, I reproduce part of it here. He says: “We have just placed upon the stage [of the microscope] a little trough filled with sea-water, in which an Eunice is disporting itself. See how indignant it is at its captivity; how its numerous rings contract, elongate, twist into a spiral coil, and at every movement emit flashes of splendour in which all the tints of the prism are blended in the brightest metallic reflections. It is impossible, in the midst of this tumultuous agitation, to distinguish anything definitely. But it is more quiet now. Lose no time in examining it. See how it crawls along the bottom of the vessel, with its thousand feet moving rapidly forwards. See what beautiful plumes adorn the sides of the body; these are the branchiæ, or organs of respiration, which become vermilion as they are swelled by the blood, the course of which you may trace all along the back. Look at that head enamelled with the brightest colours; here are the few tentacles, delicate organs of touch, and here, in the midst of them is the mouth, which, at first sight, seems merely like an irregularly puckered slit. But watch it for a few moments; see how it opens and protrudes a large proboscis, furnished with three pairs of jaws, and possessing a diameter which equals that of the body within which it is enclosed, as in a living sheath.

“Well; is it not wonderful? Is there any animal that can surpass it in decoration? The corselet of the brightest beetle, the sparkling throat of the humming-bird, would all look pale when compared with the play of light over the rings of its body, glowing in its golden threads, and sparkling over its amber and coral fringes.

“Now let us take a lens of higher power, and move the lamp in such a manner as to let its rays fall on the reflector of our microscope, and examine a few of the hairs taken from the sides of the Annelid we have been describing. To the outer edge of every foot are appended two bundles of hairs (setæ); these are far stiffer than ordinary hairs, and appear to be placed on either side of the animal to defend it from its enemies. A moment’s consideration will suffice to confirm this view, for there is perhaps scarcely a weapon invented by the murderous genius of man, whose counterpart could not be found amongst this class of animals. Here are curved blades, whose edges present a prolonged cutting surface, sometimes on the concave edge, as in the yatagan of the Arab, sometimes on the convex border, as in the oriental scimitar. Next we meet with weapons which remind us of the broad-sword of the cuirassier, the sabre, and the bayonet; here are harpoons, fish-hooks, and cutting blades of every form, loosely attached to a sharp handle: these moveable pieces are intended to remain in the body of the enemy, while the handle which supported them becomes a long spike, as sharp as it was before. Here we have straight or curved poniards, cutting-bills, arrows with the barbs turned backwards, but carefully provided with a sheath to protect the fine indentations from being blunted by friction, or broken by any unforeseen accident. Finally, if the enemy should disregard his first wounds, there darts from every foot a shorter but stronger spear, which is brought into play by a special set of muscles, so soon as the combatants are sufficiently near to grapple in close fight.”

From the use of the word “feet” in the foregoing it must not be inferred that worms have true jointed feet, like those of crabs or insects, for instance. What are sometimes spoken of as feet in the case of the worm-class are lateral warts, which carry glassy and elastic bristles in little bundles, like paint brushes; and these are partially withdrawn into a sheath, or pushed out and used like oars with a rowing motion that, all moving rhythmically, send the creature along very speedily, especially when burrowing in sand or mud. To such of my readers as possess a microscope I would advise the careful examination of these bristles, their variety of form, as mentioned by M. Quatrefages, will afford subjects for considerable study; though it is open to doubt whether they are ever used for offensive or defensive purposes.

There is a family of these Sea-worms whose members are mostly characterised by the possession of broad overlapping scales upon their backs, and beneath these are the rudimentary gills, the plates being evidently intended to create currents to supply the blood with oxygen. Two of the most-likely-to-be-met-with of these are Polynoe squamata and P. cirrata. The former is uniformly pale brown on the upper side, completely clothed with the large, loose-looking scales, beyond which the three pairs of tentacles, and the lateral organs of touch (cirri) project. It is not easy to examine this creature closely whilst it is in a living condition, it is so sensitive to the light, and ever seeking to avoid it. Its chief concern is, “where can I hide?” It possesses four eyes, and its scales are delicately fringed. Polynoe cirrata is larger, darker, and its feet protrude further beyond the edge of the scales.

The Sea-mouse (Aphrodita aculeata) belongs to this section. It is a species that prefers deeper water, but sometimes comes to shore with a heavy sea. In addition to its scales the arched back is covered with a thick brown felt, thinner in the middle, from which emerge long brown bristles and hairs of yellow and green, that are also iridescent and reflect all the colours of the spectrum.

All the worms we have been considering belong to the Class Annelida, the true worms, with their bodies formed of a long series of rings or segments. There is another group of worms, belonging to the Class Turbellaria, of much lower organization, and generally spoken of as Planarians. Most of them are thin textured creatures that appear capable of almost indefinite expansion, and, on the other hand, they have the power of contraction to a mere speck of jelly. Their voracity is in inverse proportion to their size; and the mouth is situated on the middle line of the under surface, usually not far from the centre of the body, and opening directly into the stomach. The whole of the body is covered with very fine cilia, by whose movements they appear to owe their power of gliding and swimming. Some of them have a pair of tentacles, though in some instances these are little more than backward folds of the body, and on them or in their neighbourhood is frequently gathered a cluster, or two clusters, of eye-like sensitive spots which, however, do not appear to be very perfectly fitted for visual purposes. In some cases the mouth is the only opening to the organism, and has to serve several purposes.

The student who would collect and study the Planarians must be gifted with patience and keen sight. The fronds, stems, and roots of seaweeds are suitable places to examine; also the narrowest cracks and fissures of slaty rocks, where there appears to be no room even for a fine piece of tissue paper. Where such rocks show a loosening of the laminæ, break a portion off by inserting the putty-knife and separate the flakes. You will see some delicate specimens of the conventional worm-shape, but very thin; you will see mere specks of almost transparent jelly. Lift these off the stone carefully. How? Ah, that is a difficult matter, for they are so soft that our clumsy fingers could do nothing with them; but you must be prepared for this, and bring with you a clean camel’s hair brush. With this you can pick them up, and by dipping it into a jar of sea-water, and giving a quick rotatory motion to the brush, the Planarian will be dislodged, and will probably settle on the side conveniently for your examination of it with your lens. Any slimy-looking spot of colour that appears upon a stone or sponge you should attempt to move with your brush, and in many cases it will prove to be a Planarian that may afterwards so expand as to surprise you with its beauty.

Sir John Dalyell, many years ago, described how he cut up a specimen of the common Black Planaria (P. nigra) of our fresh-water ditches, each portion of which became a complete animal; and upon this slender basis appears to have been founded the statement, which is copied in all the books, that worms of this class partly propagate by spontaneous division, in addition to their interesting egg-laying.

Dr. Collingwood, who has paid considerable attention to this comparatively neglected group, doubts this, and I think with good reason. He has never seen this division take place; and I would humbly add that I have kept large numbers of the fresh-water species for years, but never observed the phenomenon, though I have carefully watched for and really expected it to take place—as such fission undoubtedly occurs in the Sea-anemones.

One of the largest and most conspicuous of our native species is the Banded Flat-worm (Eurylepta vittata), which is marked with longitudinal black lines on a whitish ground. It has a pair of tentacles in front of the broad, flat body, which gradually tapers away to a point behind. It has a large mouth opening near the centre of the underside.

A more worm-like group is the Nemertea, which is divided into genera, founded on the number or absence of eye-spots. One of these is the Red-faced Blind-worm (Astemma rufifrons), about an inch and a half in length, with a roundish body, no eyes, and the mouth near the front end.

The Four-eyed Worm (Tetrastemma quadrioculatum) is similar in form, but larger, thicker in the middle, and with four eye-spots arranged in a semicircle parallel with the front margin.

The Many-eyed Red-worm (Polystemma roseum) has a distinct snake-like head and neck, with many eye-spots in groups around the margin of the head and towards the neck, and in the latter there are two red spots which appear to be hearts. Just below these is the mouth. Viewed laterally the head is wedge-shaped. It is to be found in rock-crevices, and among the rubbish at the roots of seaweeds on the rocks.

He is so remarkably elastic too! You may look at this living Gordian knot and see about a quarter of an inch of the head end protruding from a tight kink; you may watch the kink and certify that no movement takes place in it; yet the head moves away to a distance of five or six inches, simply by the stretching and consequent attenuation of that free quarter of an inch.

The Rev. Hugh Davis many years ago contributed to the Transactions of the Linnean Society an account of his dealings with this Planarian, and as does not often happen to contributions to that useful but technical work, it became much quoted. It was all sober fact, as became the calling of the author and the character of the eminent society to which he communicated the story; but we were greatly amused not many years ago seeing Davis’ account of its length, etc., put forward as a specimen of a “traveller’s tale,” drawn chiefly from the imagination.

Later, but practically identical accounts have been published by Gosse, Charles Kingsley, and others. Kingsley, if we remember rightly, had to defend himself from the charge of shooting with the long-bow, or “slinging the hatchet,” and in doing so he said there was so much that was truly marvellous in Nature that it was unnecessary for an author to invent lies wherewith to startle his readers. Yet the story was too much for a well-known and generally well-informed science lecturer, for on the editor of one of the snippety periodicals printing Kingsley’s account with the sensational headline, “A living fish-line,” and without acknowledgment of the source from which quoted, Mr. W. Mattieu Williams, F.R.A.S., F.C.S., requoted it in his monthly “Gossip on Current Topics,” contributed to “Science Gossip,” and headed it “Munchausen Science.” He coupled it with what he called “an equally sensational account of the latest method of disposing of the dead, by electroplating the corpse,” and concludes, “It is not my wont to be presumptuous, but in this case I do venture to suggest that for such revelations the general title of Popular Science should be exchanged for that which I have given, Munchausen Science.” Of course, Mr. Williams was a physicist, rather than a biologist, but Dr. Taylor, the editor, professed to have a knowledge of marine biology, and how he could have let Williams’ strictures pass without comment or explanation, is more wonderful than the account of Lineus.

Davis gave up the attempt to measure the living Lineus, but when it was dead he unravelled it without stretching, and found it to be twenty and two feet long. He adds: “I give it as my firm opinion, that I speak within bounds when I say the animal, when alive, might have been extended to four times the length it presented when dead. It is, therefore, by no means impossible that this most astonishing creature may have been susceptible of being drawn out to the length of twelve fathoms, or, according to the accounts of the fishermen, to thirty yards or fifteen fathoms.”

I would only add that from my acquaintance with the living Lineus, I see no occasion whatever for taxing the Rev. H. Davis or Canon Kingsley with exaggeration. Neither, I think, will my readers, when they have read the following quotation from Prof. W. C. MacIntosh’s “Monograph of British Annelida”:—“This is unquestionably the giant of the race, and even now I am not quite satisfied about the limit of its growth, for after a severe storm in the spring of 1864, a specimen was thrown on shore at St. Andrews, which half filled a dissecting jar eight inches wide and five inches deep. Thirty yards were measured without rupture, and yet the mass was not half uncoiled.”