The Sea and Its Living Wonders / A Popular Account of the Marvels of the Deep and of the Progress of Martime Discovery from the Earliest Ages to the Present Time

by G. Hartwig

Sepia.
b. Finny membrane running along the sides of the body.
c. Arms with four rows of suckers.
d. Elongated retractile tentacles.
e. Eyes.

It might be supposed that the dibranchiate cephalopods, by their swiftness, their arms, and their powerful jaws, were sufficiently provided with means of attack or defence; but it must be remembered that their body is soft and naked, and that, though well armed in front, they may readily be attacked in the rear. To afford them the additional protection they required, nature, ever ready to minister to the real wants of her children, has furnished them with an internal bag communicating with the respiratory tube, and secreting a large quantity of an inky fluid, which they can squirt out with force in the face of their foe, and which, mixing readily with the water, envelops them in an opaque cloud, and thus screens them from pursuit. But this inky fluid, thus useful to its owner, is often the cause of his destruction by man, who applies it to his own purpose, for the Italian pigment, called sepia, so invaluable to painters in water-colours, is prepared from the inspissated contents of the ink bag of a cuttle-fish. Such is the durability of this colour that even the inky fluid of fossil species has been found to retain its chromatic property. We are told that grains of wheat buried with Egyptian mummies three thousand years ago have germinated; but it is surely still more astonishing that an animal secretion, the origin of which is lost in the dark abyss of countless ages, should remain so long unaltered.

The cephalopods are scattered in vast numbers over the whole ocean, from the ice-bound shores of Boothia Felix to the open main; they seem, however, to be most abundant in temperate latitudes. Some, like the common poulp, constantly frequent the coasts, creeping among the rocks and stones at the bottom; others, like the Cirroteuthis and Ommastrephes, roam about the high seas at a vast distance from the land.

They are generally nocturnal or vespertine in their habits; they abound towards evening and at night on the surface of the seas, but sink to a greater depth, or retire into the crevices of the rocks, as soon as the sun rises above the horizon. Some are of a recluse disposition, and lead a solitary life in the anfractuosities of the littoral zone; others, of a more social temper, wander in large troops along the shores, or over the vast plains of ocean.

Possessing the organs of sense, and the means of locomotion in a high degree of development, the cephalopods may naturally be expected to be far more active and intelligent than the inferior orders of the molluscs. On moonlight nights, among the islands of the Indian Archipelago, Mr. Adams frequently observed the Sepiæ and Octopi in full predatory activity, and had considerable difficulty and trouble in securing them, so great was their restless vivacity, and so vigorous their endeavours to escape. "They dart from side to side of the pools," says the naturalist in his entertaining and instructive account of his journey to those distant gems of the tropical sea, "or fix themselves so tenaciously to the surface of the stones by means of their suckers that it requires great force and strength to detach them. Even when removed and thrown upon the sand, they progress rapidly, in a sidelong shuffling manner, throwing about their long arms, ejecting their ink-like fluid in sudden violent jets, and staring about with their big shining eyes (which at night appear luminous, like a cat's) in a very grotesque and hideous manner."

At the Cape de Verd islands, Mr. C. Darwin was also much amused by the various arts to escape detection used by a cuttle-fish, which seemed fully aware that he was watching it. Remaining for a time motionless, it would then stealthily advance an inch or two, like a cat after a mouse, and thus proceeded, till, having gained a deeper part, it darted away, leaving a dusky train of ink, to hide the hole into which it had crawled.

All the cephalopods are extremely voracious; they destroy on shallow banks the hopes of the fishermen, devour along the coasts and on the high seas countless myriads of young fish and naked molluscs, and kill, like the tiger, for the mere love of carnage. Thus they would become dangerous to the equilibrium of the seas if nature, to counterbalance their destructive habits, had not provided a great number of enemies for the thinning of their ranks.

They form the almost exclusive food of the sperm-whales, and the albatross and the petrels love to skim them from the surface of the ocean. Tunnies and bonitos devour them in vast numbers, the cod consumes whole shoals of squids, and man, as I have already mentioned, catches many millions to serve him as a bait for this valuable fish.

At Teneriffe, in the Brazils, in Peru and Chili, in India and China, various species of cephalopods are used as food. Along the eastern shores of the Mediterranean, the common sepia constitutes now, as in ancient times, a valuable part of the food of the poor. "One of the most striking spectacles," says Edward Forbes, "is to see at night on the shores of the Ægean the numerous torches glancing along the shores, and reflected by the still and clear sea, borne by poor fishermen, paddling as silently as possible over the rocky shallows in search of the cuttle-fish, which, when seen lying beneath the water in wait for his prey, they dexterously spear, ere the creature has time to dart with the rapidity of an arrow from the weapon about to transfix his soft but firm body."