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Family Octopodidae

HEAD very large; arms eight, long, all alike, more or less webbed; suckers usually in two rows; mantle supported by columns or bands of muscle.

Genus OCTOPUS, d'Orb.

Body much shorter than arms; suckers few, in two rows; arms extensible, large, webbed at base; third right arm hectocotylised; two cartilaginous stylets stiffen the back of mantle.

Octopus, Devil-fish. Polypus. (O. vulgaris, Lam.) Marine, carnivorous mollusk, of great strength. Body globose or pear-shaped, six inches to one foot long, with scattered horns on back; arms smooth, sessile, uniform, fleshy, elastic, webbed at base, three or four times as long as body; suckers not stalked, set in two rows on inner face of arm; neck short, small; head large; eyes prominent, with horn above each; skin dusky, but varies from purple to yellow and white; hectocotylised arm short, broad, flat at tip, whitish, with one or two suckers abnormally large; eggs small, clustered on a central cord. Habits, nocturnal, solitary, predatory, fighting when disturbed. Food, crustaceans, bivalves and fishes. Used as food in Mediterranean countries.

Habitat.--Rocky bottoms in shallow water. Temperate and warm seas.

This is the common octopus or devil-fish of Europe, known as "Polypus" by the ancients, and accurately described by Aristotle. It lives along rocky shores of moderate depths in tropical and temperate oceans, making its home in some suitable crevice hollowed out like a grotto, where it lies with arms and web outspread ready to entrap any bivalve or fish that strays within reach of the arms. The peculiar power of taking on a colour to harmonise with the surroundings is well developed in the octopus. Its body might well be mistaken for a part of the rocks against which it clings, and the coiling arms for the tortuous stems of seaweed on the ocean floor. The watchful eyes and the sensitive tentacles combine to bring good hunting every day to the hungry ogre, the doorway of whose cave is strewn with the bones of victims.

When no longer hungry the octopus walks abroad, sliding along the sandy bottom with all its arms flattened, the bulbous body carried aloft. Warm, quiet waters favour the propagation and general well-being of these creatures. A cold winter sends them to deep water. The spawning time is the late winter season, when the number greatly increases in the shallow water. They come in shoals or schools during January, February and March and the fishermen catch them by various means to prevent as many as possible from spawning. Though a valuable sea food in many localities, especially on the Mediterranean, in others they are counted not fit to eat, and are very destructive to the lobster and crab industry, also killing young fish so extensively as to diminish the value of the fishing industries on some coasts.

Very little is known about the rate of growth and the age of octopi. Specimens with arms three feet long are estimated to be three or four years old. This fact is quoted from the report of the Marine Biological Laboratory at Plymouth, England, published in 1899.

It is interesting to get a glimpse of the life of the octopus by watching one in captivity. Many public aquaria maintain octopus tanks. The inmate sits in a squat position, his eight arms spread out on the bottom and singularly like the rocks in colour. The body looks like a great swollen pear. The head is not unlike an elephant's, though the cruel, malignant eyes are larger.

The keeper comes to feed the octopus. A crab is dropped into the water. It seems to shudder and to realise its fate, as it settles. The octopus evidently sees and understands. The moment the crab is dropped into the tank he spies it and rushes out, his tentacles spread forward to form a hollow cone. Into the web at the base of the arms the crab is drawn. If its struggles lend any difficulty the umbrella-like cover is thrown over it, and that is the last to be seen of it. It is quick work, the tearing of the victim limb from limb. The octopus has the good taste to conceal the process from the public gaze.

It is the experience of keepers of aquaria that the curled octopus, Eledone cirrosa, is never safely put into a tank with Octopus vulgaris. A fierce cannibalistic zeal consumes the latter, and he consumes every specimen of his more gentle-mannered cousin. Even larger individuals than himself are attacked and destroyed. He apparently recognises his relative as a non-resistant. and fears no opposition.

It is in his conflicts with man himself that the octopus earns the name of devil-fish. The cruel, vindictive expression of the eye seems to be a true index to the spirit with which the animal comports itself in combat with mortals. Fishermen dealing with octopi always carry axes to cut loose the arms if they are fastened on the boat. The power exerted by the suckers is tremendous. An octopus with a few of its arms holding on to the rocks has a few free with which to seize a swimmer. It is easy to bind him hand and foot, An over-reckless man is often drowned in two or three feet of water, overpowered by an octopus with arms of four feet spread and a body scarcely as large as his fist. Scientists without experience of this cephalopod tempt death in an effort to "collect" specimens of this sort, and need help to prevent the octopus from collecting a man. "Mansucker" is one of its local names. It treats all victims alike, except that it picks the bones of vertebrates.