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CHAPTERS ON CUTTLES.

No. 2.

BY W. H. BOOTH.

N geological times the Tetrabranchiata were the more abundant forms, as testified by the numerous species of ammonites, orthoceratites, and others, whilst the Dibranchiata were comparatively scarce, and very poorly represented. Proceeding, we find that the two-gilled are separated into two sections, A and B, the first of which (A) contains cuttles which have eight arms, and is hence termed Octopoda; whilst the latter section contains cuttles which, in addition to the eight arms, possess two long tentacles, and so the section goes by the name Decapoda. The first in order of the eight-footed cuttles is the Paper Nautilus, Argonauta (so called from the ship Argo, and vavrínos, the Greek for a sailor), a species which is not represented in British waters. From the times of the ancients the Paper

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Fig. 2. Pen of ditto.

Fig. 1. Common Squid. (Soligo vulgaris.) Nautilus has been a subject of conjecture and romance. Pliny and Aristotle both mentioned it in their works, and failed not to weave a most fanciful story concerning it. They supposed that two broad arms, with which the animal is equipped, were used for sails, and other arms for oars, so that the Argonauta navigated its vessel like any skilful seaman. Even two of our own poets have fallen into the same error; Pope's lines,

"Learn of the little nautilus to sail,

Spread the thin oar, and catch the driving gale,"are perhaps the best known; but James Montgomery gives us some verses to the same effect in his

Fig. 5. Horny jaws, or mandibles, of Cuttle-fish.

People very naturally thought from this that the shell was not the production of the animal they found in it, but that it had been formed by some other creature, and seized as a convenient dwellingplace by the cuttle. Madame Jeanette Power, residing at Messina, conducted several experiments to test the truth of this, her conclusion being that the shell was the veritable production of the Argonauta. Having collected a number of living specimens of Argonauta Argo, the Mediterranean species of Paper Nautilus, this lady broke their shells in different degrees, and was rewarded by seeing some apply their broad dorsal arms to the fractures, and deposit a thin film of shelly matter, covering the broken parts. In about thirteen days, this became quite as hard and thick as the unbroken part, but

slightly more opaque. Should the whole of the shell be broken, the animal is unable to reconstruct a new one, and dies. The eggs are kept within the shell, and are so clustered around the spiral, that when the animal propels itself, keel foremost, they are not exposed to the swift current of water, which otherwise might seriously interfere with their due incubation. The shell, during the life of the animal,

namely, by the expulsion of the water from the gills; they also crawl along the bottom of the sea. The Argonauta is very abundant about Messina, and even enters the port. It is most plentiful about autumn, and frequents muddy spots. Madame Power was inclined to believe that the Argonauta really did use its two dorsal arms as sails, but another close observer of these interesting creatures, M. Sander Rang, at Algiers, altogether discountenances the idea. He says, "Watching what took place around the Poulp (another name for Cuttle), which we left contracted in the Argonaut shell, we saw it extending itself from its shell and protruding six of its arms; then it threw itself into violent motion, and travelled over the basin in all directions, often dashing itself against the side. In these different movements the body leaned a little

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Fig. 8. Common Sepia. (Sepia officinalis.)

towards the forepart of the shell, aud the long slender arms, much extended and collected into a close bundle, were carried before it, as well as the tube, which showed itself open and protruded. The locomotion was effected in the ordinary manner of Poulps, backwards, by contraction of the sac, and expulsion of water through the funnel." Another species of Paper Nautilus, Argonauta hians, is found on the west coast of Africa and in the Chinese seas; but although it has been discovered in a fossil state in Piedmont, no living species have been taken in the Mediterranean. Argonauta Argo attains the largest size of all the Paper Nautili, the shell sometimes exceeding nine inches in diameter; most specimens of other species would average about three inches.

The next cuttle which we shall examine is the Octopus (or, octo, eight, and ove̱, pous, a foot), or Poulp. Many are the names that have been given to this species,-Sucker, Man-sucker, Bloodsucker, and Devil-fish, being amongst them. A species of this genus was the celebrated Polypus of the ancients, performing all sorts of wonders and terrible deeds. As I now sit, there are three of our English Poulpes, Octopus vulgaris, staring at me with their huge dark eyes, and in their present condition looking inexpressibly ugly. These three creatures I procured a few months ago, and in order to be able to examine their organization more closely, had them immersed in spirits of wine, and securely corked up. As our English Octopus is as good a representative of its kind as any, we will take it as our example. Many are the little adventures I have had with the Octopus. By going out to its haunts, several opportunities of seeing it in its many different conditions have been offered to me. For a general appearance of the animal I must refer my readers to the illustration, merely observing that when in the following lines any mention is made of "ventral or dorsal" sides or feet, by "dorsal" is meant the side on which the funnel is situated; and by "ventral" the opposite. As its name implies, the Octopus has eight fleshy arms or feet, which on an average are about twice the length of the body, are very muscular and flexible, and taper down to a point little thicker than ordinary twine. Along the whole under-surface of these arms is situated a series of circular discs or suckers, of strange construction. These suckers are fixed in pairs, except the first half-dozen near the mouth, which are placed immediately over each other; they form the chief means by which the Poulp is enabled to seize its prey, and are of curious construction. To describe them, I cannot do better than liken them to the pneumatic pegs so largely used by photographers, and for fastening on to shop-windows. Like these pegs, the suckers have around the outside a broad soft band, which in the case of the pegs is made of india-rubber, and in that of the Octopus of a fleshy substance. This band then leaves a cavity in the centre, and to this hollow is attached a muscular piston, exactly fitting the aperture, capable of being worked up and down at the will of the animal. When, therefore, the surface of this sucker is pressed against any substance, the withdrawal of the piston creates a vacuum, and powerful adhesion takes place. Having seized its victim by encircling it with his arms, the Octopus drags the unfortunate animal to the powerful horny mandibles with which it is furnished, and makes short work of it. These mandibles are similar to the beak of a parrot, and are of great strength, being able to break through the hard shelly covering of crabs or lobsters. Endued with so much strength, the Octopus makes

its jaws very effective weapons, such that a close acquaintance with them when the animal is alive is far from desirable. A Mr. Beale has described an encounter he had with an Octopus in the Bonin Islands, where he was searching for shells. It seems that Mr. Beale, seeing one of these strange-looking monsters on the rocks, endeavoured to stop its progress by pressing on one of its legs with his foot. As the animal still persisted in its attempts to escape, he caught hold of one of its arms, and tried to disengage it from the rocks, when the animal, evidently enraged, loosing its hold from the stones, sprang on his arm, and prepared to bite it with its beak. Had not a friend been at hand, the consequences might have been serious; but, fortunately, a companion came up, and released Mr. Beale from his ferocious assailant by means of a large boat-knife. Thus we see, the Octopus when enraged does not hesitate to attack man himself, in self-defence. The number of suckers possessed by our common Octopus falls but little short of two thousand; their application to the human skin is said to cause pain and inflammation. My own experience has not led me to verify this statement; for, although in searching under the rocks, in such places as the Octopus loves to haunt, I have often had my hand seized by its tenacious arms, yet on releasing myself, no subsequent feeling of pain whatsoever has resulted. The cold, slimy grasp of this small creature is by no means pleasant; how much more so must that of the larger species be? The food of this cuttle consists chiefly of mollusks, which it collects and brings to its den. The fact of the Poulp having a regular den is rather curious, as one would have supposed that an animal so low in creation, and of such a predatory nature, would devour its prey on the spot. The place chosen for the den is generally an isolated piece of rock, situated on the sand, where the hollow which is generally to be found round about such stones, forms a convenient place for the Octopus to stow itself, and deposit its booty. The large otter-shells (Lutraria), with those of the genus Tapes, and various others, form its favourite food. Often after bringing the creature out of its den, a feat best performed by means of a large fishhook attached to a stick, many excellent shells, with the animals still undevoured, may be found. An amusing fact is that the Octopus nearly always has a number of hangers-on, in the shape of small Hermit Crabs (Pagurus), mostly tenants of a common top-shell (Trochus cinereus). These parasitical hosts, on being disturbed, present a most ridiculous spectacle in their hurry to be off. Endeavouring to clamber up the bank of sand, they naturally only bring down a heap of it with themselves, and to see twenty or more of these droll little creatures rushing franctically up, and then falling back again pell-mell, is most laughable. As the Octopus is addicted to getting more food than

it can possibly stow away in its capacious stomach, these small gentry act as its scavengers, and clear away the remains of each feast in the neatest manner. The skin of the Poulp is furnished with several colour-glands, which enable the animal to vary its tint in a manner very similar to that of the Chameleon. In a chase after one which I had disturbed, I was pleased to notice that when darting over sandy ground, its colour became very much lighter than before, whilst directly it approached a rocky or shingly portion of the coast, a darker hue pervaded its body. Darwin, in that most interesting of books, his "Journal of a Voyage Round the World," gives a pleasing account of the Octopi at St. Iago. After a description of their rapid motion, and methods of escaping notice, he goes on to say that any part of the skin of the Octopus, on being subjected to a slight shock of galvanism, becomes quite black: a similar effect, but in a less degree, is produced by scratching the skin with a needle. These clouds, or blushes, as they may be called, are said to be produced by the alternate expansion and contraction of minute vesicles containing variouslycoloured fluids. This gentleman whilst looking for marine animals, with his head near the rocks, was more than once saluted by a jet of water, accompanied by a slight grating noise. On examination, he found out that this was a cuttle which, though concealed in a hole, thus led to its discovery. "That it possesses the power of ejecting water," says Darwin, "there is no doubt, and it appeared to me that it could certainly take good aim by directing the tube or siphon on the under part of its body." As the Octopus darts along, the dilation and subsequent contraction of the sac is very plain, and the rush of the water through the funnel is also easily discernible. Its first action on being disturbed is to discharge some of the ink with which it is furnished, in order to cover its retreat. This ink is of a more viscid nature than ordinary writing ink, and when spurted forth does not become generally suffused, but forms a dense cloud about the animal, and ultimately settles down to the ground. Even if all its supply of ink has been discharged, the Octopus in a few hours has a full battery ready for use again. The flesh of the Octopus is sometimes used as food, but only by the poorer classes of the seaside population. | In the Levant, (according to “A. M. B.,“ SCIENCEGOSSIP, June, 1865), a species of Octopus, going by. the name of Octopoda, is very troublesome to the fishermen, but much esteemed as an article of consumption. The method of preparing it for table in those Eastern quarters, is to beat it for an hour or so against a rock, and afterwards serve it up as a fricassée, or otherwise. Horrible to think of, some savages eat the Octopus raw-what a strange taste is this! In the Octopoda, no shell, internal or external, is visible; they are said to be highly luminous in the dark, and Pliny, quoting Bartholinus, says

so great was the luminosity proceeding from them ut totum palatium ardere videretur." There are upwards of forty species of Octopus known; their eggs are usually deposited in the spring on seaweeds or empty shells.

Their

We now come to Section B, the Ten-footed Cuttles, or Decapoda. The chief peculiarity of the animals comprised in this section consists in their having, in addition to the eight arms such as are possessed by the Octopus, two long tentacles, whose ends are expanded and furnished with suckers. These tentacles, in all but one genus, can be drawn within a sort of pouch situated below the eyes; they are of use to the cuttles for seizing their prey, and also for mooring the animals fast to the rocks, when the stormy weather would threaten them with destruction. The suckers of cuttles of this section are of a different description to those before mentioned, being what is termed pedunculated, and more prominent. The dissimilarity chiefly consists in their being surrounded by a horny ring. bodies are rather elongated, and contain a shell which in some species is calcareous, and in others horny; it is not fastened to the body of the animal, but contained loosely in the mantle. The Decapods. are mostly gregarious, and frequent the bigh seas. in great numbers, moving about periodically from. the northern and southern zones. They are divided into four families, the Teuthida, Belemnitidæ. Sepiade, and Spiralida, a few genera of each of which we shall examine in their order. Our first decapod, a member of the Teuthida, or Calamaries, is a very abundant animal on our coasts. Reference to the illustration of the Squid (Loligo vulgaris), for that is the creature's name, will show that in this species the arms are very short, and the body much elongated. An expansion of the mantle on each side of the caudal extremity forms a pair of fins, by means of which the Squid is able to swim very swiftly. The most curious part of the animal is its shell, or pen, as it is called, a horny substance analogous to the bone in the Sepia. This pen may be seen figured, together with the illustration of the animal; it resembles an ordinary quillpen in general shape, and acts as a sort of backbone to the creature. Several "pens" have been found in the body of a single squid, so that it is thought that they increase with the age of the animal. From possessing this peculiar appendage, the Squid has had the name of Sea-pen given to it. The pen is of a horny transparent substance, and has been found in a fossil state. Like most other cuttles, the Squid is furnished with a supply of ink. From these two characteristics, I think it might very appropriately be called the "Pen-and-Ink Cuttle." A lady at Lyme Regis, Miss Mary Anning, was the first to discover the ink-bags of the Loligo in a fossil state in that neighbourhood. They are found distended just as when they formed parts of the living animal

and retain the same juxta-position to a horny pen, which the ink-bag of the recent Loligo bears to the pen within the body of that animal. The state of preservation of the pens is such as to admit of a close comparison of their internal structure with that of the present living Loligo. Similar remains of the pens and ink-bags of animals of this genus are frequently found in the Lias shale of Aalen and Boll, in Germany. The Squid is the animal used for bait in the Newfoundland cod-fisheries, and is also occasionally used for the same purpose by the fishermen on our own coasts. The manner in which it is caught is as follows:-A party of sailors go out in boats to a place the Squid is known to frequent, armed with an instrument know as a "Squid-jigger." This consists of a number of large hooks fastened together so as to form a circular chevaux de frise. To catch the Squid, this weapon is fastened to a line, and dropped in the water without any bait, but by giving it a continuous up-and-down motion, all the Squids that come near are hooked and secured. On being brought to the surface, they discharge a torrent of ink, so that to avoid being deluged with the black stream, a little dexterity is needed. The Loligo has sets of suckers arranged in two rows along its arms, as the Octopus; the suckers on the .extremities of the tentacles are situated in fours. This is a well-distributed genus, being found in the Atlantic, Mediterranean, North Seas, and the Southern Ocean. Of another genus, Sepiola, an abundant little species is found in our common Sepiola (Sepiola atlantica). In this cuttle the body is short and dumpy, furnished with two comparatively large-sized fins situated diametrically opposite one another on the sides of the animal. The pen is very similar to that of the Loligo. Gosse, in his valuable work on the aquarium, gives a vivid description of this animal, portraying in the most lively terms the various evolutions it is seen to perform when kept captive in an aquarium. A striking feature in the animal is the propensity it has for burrowing; by directing its funnel towards the sand, and then expelling the water from its gills, it scoops out, in the most perfect manner, a small hollow, where it snugly ensconces itself, leaving but little of its body visible.

Passing over several other genera, we come to the Onychoteuthis (övvž, onyx, a claw, and reveis, teuthis, a calamary) or uncinated calamary. This formidable genus, in addition to the suckers on its arms, is furnished with a terrible set of horny hooks on the expanded extremities of its long tentacles. By means of these hooks it is better able to retain its hold on fishes, as, from the slimy nature of their scales, it would frequently be difficult to get the suckers into action. As if not sufficiently armed with its suckers and hooks, this calamary is also furnished with an adhesive disc, immediately below the hooks on the tentacles; and

by bringing these two discs together they become firmly locked. The victim once embraced by these has no hope of escape left, and is pressed against the jaws of its destroyer by means of the arms. The next genus, Enoploteuthis (ivoñλoç, enoplos, armed, and revic), is a still more formidable one, for in it all the arms are furnished with hooks. Professor Owen says that the natives of the Polynesian Islands live in great dread of cuttles of this genus. One species found dead there by Sir Joseph Banks, measured over six feet in length. One arm of this identical calamary is still preserved in the museum of the College of Surgeons, where it may be inspected. Another genus, Ommastrephes (õμμa, omma, the eye, and orpiow, strepho, to turn), much resembles the Octopus in general form. The eyes are very conspicuous, and the arms welded together up a considerable part. Animals of this genus, as well as those of Loligo, are used in the cod-fisheries. The former have the power of leaping a great height out of the water. Mr. F. D. Bennet mentions that these calamaries were very numerous in the vicinity of the Sandwich Islands, where they are extensively used as food, their flesh having somewhat the flavour of a lobster, and being considered a delicacy. In that locality the Flying-fish and this Calamary were most plentiful during a calm, when they were seen leaping out of the water. The fate of the Ommastrephes appears to be somewhat similar to that of the Flying-fish; for whilst leaping out of the water to escape their aquatic pursuers, they fall a prey to birds, who diligently watch for an opportunity to seize them when out of their native element. Some few, being thus pursued, leapt up to a considerable height above the bulwarks of the ship in which Mr. Bennet was, and fell on the deck. Having now examined a few of the genera of the Teuthida, we proceed to the next family, the Belemnitide. This family is probably better known to our geological than to our conchological friends, as no living species exists, and all our information as to it is drawn from fossils. The shell of the Belemnites, which is nearly the only part ever found, was an internal one, somewhat similar to that of the Sepia. In the middle is a sort of cup, termed the alveolus, divided into compartments, which are connected by a tube. The alveolus is protected by a calcareous incrustation (rostrum), rather elongated, whose function was probably to guard the animal from the shocks to which it was exposed as it swam backwards. It is this rostrum which is discovered so very frequently in a fossil state. An interesting article on the Belemnites, by our much-esteemed editor, will be found in the volume of this magazine for 1872. It is embellished with several illustrations, which will serve to make their construction more manifest.

Leaving the Belemnitide, we now proceed to

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