Page:The American Cyclopædia (1879) Volume XVI.djvu/604

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580 WHALE opening a free passage from the longs exter- nally through the blow-holes, even though the whole head be submerged and the mouth tilled with water. In the expulsion of water (which is denied by some and admitted by others), it is forced into the nasal cavities while the ani- mal performs the act of swallowing, the pha- rynx being closed to prevent its passage be- yond the proper point, and the forcible con- traction of the muscles surrounding the pas- sages sends it out in a jet ; expiration, carrying with it a jet of vapor, is performed in a similar manner. Though all are carnivorous, the stomach has from three to six compartments. In order to provide a constant supply of arte- rial blood during submersion, there are plexus- es of arteries within the chest near the spine. (See DOLPHIN.) The whales embrace the lar- gest of living animals, and have been known in all ages, but were generally and naturally enough regarded as fishes even by naturalists to the time of Linnaous ; they are, however, true mammals, warm-blooded, air-breathing, bring- ing forth their young (usually one) alive, and suckling them for a considerable period by means of two abdominal mammoo. They mostly occur in large shoals in the arctic and antarctic seas, and are often seen sporting on the surface of the ocean ; that the pectorals are not loco- motive organs, but balancers and rudders, might be supposed from their small size when com- pared with the tail ; when life is extinct they fall over on the back ; the young are also held by these limbs. In the lalanida or baleen whales there are no teeth in the adult, but there are in the embryo, though from the early ossification and coalescence of the groove in which they lie, they do not come into view ; the mouth is provided with numerous plates of the horny substance well known as whale- bone or baleen ; along the centre of the palate runs a strong ridge, and on each side of this a wide depression along which the plates are inserted ; these are long and flat, hanging free, placed transversely, with their sides parallel and near each other ; the base and outer edge are solid whalebone, but the inner edge is fringed, filling up the interior of the mouth and acting as a strainer for the food, which consists chief- ly of the small swimming mollusks and medusa) or ielly fishes. The baleen rarely, if ever, swallows anything larger than a herring ; shoals of these small creatures are entangled in the fibres of the baleen, the water which does not escape by the mouth being expelled by the blow-holes; though the cavity of the mouth is large enough to contain a ship's long boat, the opening of the gullet is not larger than a man's fist. The lower jaw has neither baleen nor teeth, but has large fleshy lips, within which the upper is received when the mouth is closed. In the genus balcena (Linn.) there is no dorsal fin ; the baleen whales with a dorsal fin have been described under RORQUAL. The right or Greenland whale (B. mysticetm, Linn.) attains a length of 60 to 70 ft., the tail being 5 or 6 ft. long and 20 to 25 ft. wide ; the general color is blackish above and grayish white below ; pectorals 8 to 9 ft. long and 4 or -6 ft. wide ; the mouth is 15 or 16 ft. long, 6 to 8 ft. wide, and 10 to 12 ft. high inside, presenting a sig- moid curve when shut ; the eyes are not larger than those of an ox, with a white iris, and placed about a foot obliquely above and behind the angle of the mouth ; the tongue is soft, thick, fatty, and very slightly movable ; the tail is of immense power. The ordinary rate of progress is 4 or 5 m. an hour ; they swim not far beneath the surface, and throw them, selves in sport entirely out of water ; they are fond of immersing the body perpendicularly and flapping the tail on the surface, making a sound heard for 2 or 3 miles ; they usually come up every 8 or 10 minutes, but can remain down half an hour or more ; they generally keep on the surface about two minutes, during which they blow eight or nine times, and then Bight Whale (BaUcna mysticetus). descend; they feed swimming just below the surface, with the mouth wide open. They are found in most parts of the arctic seas. Ges- tation has been variously placed at 9 to 15 or 18 months; the young measures at birth 10 to 14 ft. in length, and is tenderly cared for by the mother for a year or more; during nursing they gently roll from side to side hori- zontally, so that each in turn may have an op- portunity to breathe; the young furnish but little oil, and are never struck by the harpoon unless to capture the mother by means of her affection for her progeny. According to Prof. J. Wyman, in an embryo 6 in. long, the tail was rounded as in the manatee, with a vertical crest above and below it, and the thymus gland very large, almost enveloping the heart. The southern or Cape whale (B. australis, Des- moulins) attains a length of 50 or 60 ft., and has a relatively smaller head than the northern species ; it inhabits the southern ocean, gen- erally near the coast, and In comparatively shallow water; it goes up the Pacific even to Japan and Kamtchatka, the Atlantic as far as the United States, and all along the African coasts ; it is hunted in summer, when the shoals come near the shore to produce their young; the principal fisheries are about New Zealand and S. Africa. The family physe-