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MIMICRY AND OTHER HABITS OF CUTTLES.

I have no desire to raise the question as to how certain colors change in the skin of the cuttle-fishes, whether by volition or otherwise. My purpose is only to record facts. Just now I am only touching the fringe of a very great subject, although Mr. Bate began it so long ago. Like my article on the crabs, this also will be written on hypothetical lines-although showing voluntary actions in these creaturesleaving to the future the final decision.

These cephalopods are true mollusks, although they make the nearest approach of all known creatures to the vertebrate forms. Here, for the first time, we have a distinct brain enclosed in a brain pan of jelly or cartilage answering to the skull in the higher forms of life.

Beside this rudimentary skull, a few of this species have also a spinal column in shadow; for I think it doubtful if it is in its initiatory stage. In some it is in the form of a clear, flexible gelatinous pen or feather, strong enough to keep the animal in shape. In others it takes the figure of an oval shelly plate, carrying on one of its surfaces a quantity of very thin shelves which are kept apart by pillars so fine as to be microscopic; and, although formed of hard, stony matter, by this arrangement the plate is so light as to float in water, thus giving a needful buoyancy to the creature.

In animals so nearly allied to the fishes, this question arises with those who intimately know them: if sense were compared with sense in the two races, which would show the highest development? And it has been inferred that the cuttles would take the highest place. But seeing that the fishes

'Mimicry and Other Habits of Crabs; The Living Age. July 7, 1900.

1

seem to possess more senses than the cuttles, this might give the fishes an advantage in fighting the battle of life. Here, I purpose to take the faculties of the cuttle in succession."

The Eyes consist of a single pair, one on each side of the head, and are large and brilliant-superior as an organ of vision to those of many of the vertebrates, and presenting peculiarities of great interest to the anatomist.

The Ears are two chambers or cavities behind the eyes, in each of which is suspended a sac containing a clear fluid and an otolith or ear-stone. Cuttles are very quick of hearing; and great caution is needed when trying to catch them, so that no noise may be made.

The Taste.-In the mouth is a large fleshy tongue, the structure of which indicates a great development in the sense of taste; in fact, we know of no marine animal which has such facilities for the enjoyment of its food.

The Smell.-Below, or behind, the eyes are small cavities with raised borders, containing a soft wart-like substance, and supplied with special nerves. These appear to be organs of smell.

The Feelings, or Touch.-These are found in the whole skin and lips, and especially in the arms and tentacles.

Beside this, cuttles have characteristics which are peculiarly and wholly their own.

Thus they have but two bones or horny developments connected with their structure. These are in the upper and lower jaws, in the form of a parrot's beak, and are formidable weapons when in use, being so hard, and attached to muscles so strong, that

2See Gosse's "Manual of Marine Zoology for the British Isles," p. 133.

they can easily break through the back and claws of crabs.

In feeding, unlike the case of most animals, the lower jaw is a fixture, and the upper jaw opens and closes the mouth, giving the creature great command of grip when attacking large objects.

Then they are head-footed animals; and when walking on the floor of the ocean they are very different from most other creatures, in having their head and heels so close together, and their mouth and eyes so near the dirt and weeds of the sea-bottom.

Then their blood is either violet, green or transparent; and, I believe, never red. And their general habits, including mimicry, are so intense and extreme that I purpose to review several of these creatures individually. My first case will be the

ELEDONE OCTOPUS.

These invertebrates are fairly plentiful off the Cornish and Devon coasts and breed freely there; their eggs are enveloped in a glutinous whitish-gray finger-like case; and in the early spring they are often attached by the parents to the fishing implements of the crab fishermen, in bunches of from a score to thirty in number.

The young, in breaking the sac in July or August, are perfect in form and color; and are about the length of rice grains, but a little broader in size. I have known them squirt ink the moment they were afloat.

Full-grown specimens seldom exceed two feet six inches in their extreme grip; and having only a single row of suckers on their arms they cannot be confounded with the larger varieties. Their food is generally small crustaceans, but when hungry they will embrace all kinds of young fish life.

In the winter months when food is scarce, they are caught on the fisherman's hook, and when thrown into the

boat there is no end to their wanderings; sometimes they will climb up the mast a considerable distance, or, if allowed, will quietly creep over the side of the boat and drop into the depths below.

Their enemies are all the predatory fishes and larger crabs, and over and above their sepid secretions their mimicry manifests itself in imitating their surroundings to avoid these foes, for it is certain that but few species in the great deep afford its inhabitants such pleasant food as do these cuttles; and as a consequence all the hungry forces of the sea are aiming at their destruction.

That they may meet these enemies the great Designer has supplied cuttles with compensating balances equal to their wants for the preservation of the race. First, they possess an elaborate facility for instantly changing their skin into a great variety of colors, which seem to be under the control of the muscles, and held in or under the cuticle in sacs or vesicles. This power is always used by the animal for assimilating or blending its colors with its environment. And secondly, when these deceptive colors fail and the creatures are really discovered and attacked by their enemies, they are furnished with an ink bag and siphon, whereby they can instantly cover their pursuers in a cloud of darkness some two or three feet square; and while thus enveloped the eledone quietly drops out of sight.

Considering the home and life of these creatures, there can be no doubt that in our shallow waters, where masses of red, olive and green seaweeds abound with their varying shades, interspersed here and there with jutting rocks and neutral sands, at times when the sea is clear and the sunshine is on them, they must present vistas of harmonious and unique beauty. And further, outside the

laminarian zone or the range of the sea-weeds, amid the many varieties of the sea-bottom, where the hoary rocky pinnacles pierce up through the blue sea, where patches of gray sands lie here and there in contrast to these looming heights and stretching shadows, and where all is toned and softened by the sun throwing its dim blue light on countless millions of red Gorgonias, creamy Alcyonidæ and white bivalves, in the sometime quiet of this oceanic sylvan wilderness, there must be a dreamy condition of stillness and color almost impossible elsewhere.

In localities like these the eledone lives. To match and blend with all these gradations of tints and hues, when wandering through these vales of beauty, so as to be prepared for the worst and to evade their piratical and plunderous enemies, these cuttles have at will a great variety of vanishing and fleeting colors, many of which I have seen displayed. Among them I have noticed a bright mahogany on the back with a whitish blue on the chest; also reddish streaks running down the back and sides, filled in with bluish gray, the latter color covering the under part of the mantle; also a chocolate red on the back with a green chest and surroundings; then a French gray color on the back mottled with a creamy white throughout.

I have seen, too, a mottled skin of salmon color and gray with flashes of spotted green, the

green showing brightest on the web between the arms. Another color has been a heliotrope on the back, with peacock blue mixed with salmon color below. And these were all made to move and shade into each other as freely and gently as the blushes on a lady's face, while at other times they could be so suddenly

In some places the bottom of the sea is covered as thick as a fern-brake with these beautiful flexible corals.

mixed and fused together as to be beyond any description of mine. I now come to the

OCTOPUS VULGARIS.

These massive cephalopods live among the rocky precipices under the sea; and from cavern and crevice are ever ready to pounce out and assault their enemies. I cannot imagine any creature more vindictive, violent or cunning, or whose embrace is so much like the grip of death, relentless, sure, abiding; once felt, ever to be remembered.

On our coasts we have them with tentacles stretching seven feet, with a thousand suckers on their eight arms, some of whose discs will easily cover a penny.

The late Frank Buckland once stated that there was no difficulty in a creature like this holding a man down in the sea and drowning him. Their enemies are most of the fishes with predal habits, with whom they often battle successfully; for beside the immense muscular power centred in these limbs, they have their sucking cups, which are none other than tough leather-like pistons and cylinders attached to these flexible arms, which can surround any object, and whose grip and action are further regulated and intensified by using, at will, the weight of the ocean and atmosphere above.

Then they have their ink bag and siphon, with which they can half suffocate their adversary, besides enveloping him in a cloud of pitchy darkness which no eye can penetrate, while they are in clear water and can retreat at leisure.

Their favorite food is crabs and lobsters, whose hard backs they can easily pierce with their bony parrotlike beaks.

On the coasts of Cornwall the largest forms are readily caught on the fisherman's hook; and an objectionable com

panionship is sometimes the result. This was the case recently near Mevagissey. On a dark autumn night, in a small boat, Mr. Samuel Kelly was fishing on the high rocks off the Griffin Headland, when one of these devil-fish took his bait, and with the usual effort was hauled on board. But his difficulty was to get the hook to continue his work, for he had been successful in catching several pollack and conger, and the moment he touched the brute some of its clammy tentacles would embrace his arm, holding him to the spot, for its other arms were fastened around the thwart. Soon the beast became so violent that it really made him fear it. He made a supreme effort to get his hook, but the creature fastened its largest suckers on the back of his right hand, and in the battle he had to drop his line and with the nails of his left hand to dig the suckers out of his flesh, for they seemed to bury themselves there. After this experience, there was no more doubt or indecision in the fight, for seizing a sharp knife he quickly cut the hook from its hold, upon which the cuttle crept away to another part of the boat. But this did not finish Mr. Kelly's night work, for on again throwing out his line he had a still heavier haul, and when it came to the water-line he could not get it an inch further, although he used all his strength, for the line was new and stronger than he could break.

In this dilemma he had to hold on tight, and on looking over the side by the aid of a flickering light he found himself glaring into the eyes of another devil-fish, and a much larger one than the first. He further found that the creature had taken the boat for its

'Mr. Samuel Kelly is a man to be relied on. He has a school in Mevagissey, under the Cornwall County Council, for teaching youngsters the art of making knots and splices, sail and net-mending, etc. Beside his evidence, I have many other proofs from other fishermen of the audacity and violence of these creatures.

enemy, and was attacking it with all its force, its tentacles embracing the stern on the one hand, and running forwards to near the middle section on the other.

On thinking over his recent troubles with its neighbor, and the waste of time likely to ensue in a still longer encounter with a stronger brute, he decided not to risk another fight, but to use the advantage of its violent onslaught on the boat. Taking his knife and watching his opportunity, he finally cut the hook out of the intruder who, on being liberated, soon dropped out of sight.

The next day I verified most of Mr. Kelly's statements. The arms of the dead octopus in the boat stretched over seven feet, and on the back of Mr. Kelly's hand was a very black round bruise about half an inch in diameter corresponding with the inner circle of one of the largest suckers of the dead octupus. Since then he has caught several of these cuttles, and one whose arms stretched over six feet and a half. In our waters none of these headfooted mollusks have been known to take human life, but it is scarcely questionable, if favorable opportunities presented themselves, that they would do so. In 1879 one of the attendants of the Scarborough Aquarium was attacked by only a small octopus when cleaning out a tank. The experience might have ended fatally had he been in the sea with a flood tide. As it was, he had to make his exit, leaving his boot (by which the creature held him fast) behind him." But there have been occasions in other seas when the worst has happened, and men have been caught in the slimy folds of gigantic

A fact that should be known by all persons who have anything to do with the sea, is that the octopus is easily mastered by being tightly gripped by the throat. When this is done, its tentacles will instantly relax their hold.

See Wylde's "Royal Natural History," p. 762.

cuttles, which have held them on or dragged them to destruction. Sir Grenville Temple tells us how a Sardinian captain, while bathing at Jerbeh, was seized and drowned by an octopus, his limbs being found bound by the arms of the animal, although only in four feet of water; while Captain J. M. Dens, a French navigator of repute, states that, when off the coasts of Africa, three of his men were scraping the sides of his ship on a fine day when they were attacked by one of these violent creatures, which drew two of them away under water in spite of every effort made to save them, while the third who was rescued died during the night. In the fight one of the creature's arms was cut off, twenty-five feet in length, and with suckers on it as large as pot-lids. Should there still remain a residuum of doubt in any mind respecting the existence of gigantic cuttles, this will be dispelled by the following fact recorded by the Rev. M. Harvey, of St. John's, Newfoundland. On October 26, 1873, two fishermen were out in a boat near the eastern end of Conception Bay. Observing a floating object on the water they rowed towards it and struck it; on which it immediately shot out two vast tentacles around the boat, as if wrestling with an antagonist. Fortunately, they had a hatchet on board with which they cut them from the creature, which after blackening the sea with its ink, soon made off. One of these magnificent fragments was measured by Mr. Alexander Murray, geologist, and Professor Verrill, of Yale College, Connecticut, who found it to be seventeen feet long and three and a half feet in circumference. This fragment is now preserved in St. John's College, Newfoundland. Since then scientists have further considered the subject, and concluded that this

"See Henry Lee's "Sea Monsters Unmasked," p. 44. This work gives a mass of facts respecting LIVING AGE. VOL. VIII. 433

beast with its tentacles could not have been less than forty-four feet long.'

Reverting to the British octopus, I may further state that its mimicry is very great. The colors it uses run through deep chocolate, dull red, brown and gray, and it has the power of so arranging these hues that in the shade and cover of the dark rocks it is almost unseen by any eye, which facilitates its easily worrying a stranger, pouncing upon its food, or hiding from its enemies. Its change from one color to another is almost instantaneous, and the body can be mottled with the whole of these tints just as quickly.

I once saw a tank cut in the rocks on the open coast near low water and covered with many folds of iron netting, in which were kept twenty of these cuttles. Around the sides and bottom grew the dark olive laminarian seaweeds and on the rocks under them clung a stunted reddish-brown flexible coral; this they always rested on and imitated; and were always of a reddish-brown hue. They lived in seeming harmony and when a violent storm broke in the cover they did not care to leave it, but remained there for some weeks after. Their walking power is also considerable, and on the sea-bottom no doubt they often approach the object of their attack in this manner, accommodating themselves to the vari ous colors surrounding them as they near the quarry.

The fishermen see much of their walking and climbing powers and coloring faculty, when caught and thrown into the boat, for the cuttles often go from stem to stern in search of shelter, and more than once, while the fishermen were busy, I have known them, when very valuable for aquarium purposes, quietly slip over the side and drop away to the depths, much to the chagrin of the fishermen.

large cuttles. Also see Knight's "Pictorial Museum of Animated Nature," p. 173.

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