ORDER CETACEA.—WHALES.
Whales—Vulgar Notions—Characteristics External and Internal—Larynx—Tail—Skeleton—Classification—THE TOOTHED WHALES—ZEUGLODONS—SQUALODONS—PHOCODONS—RIVERDOLPHINS—SUSU,ORGANGETICDOLPHIN—Description—Habits—Teeth—INIA—PONTOPORIA—ZIPHIOIDWHALES—CUVIER’SWHALE—VANBENEDEN’SWHALE—SOWERBY’SWHALE—NEWZEALANDBERARDIUS—BOTTLEHEAD,ORCOMMONBEAKEDWHALE—SPERMWHALES,ORCACHALOTS—SPERMWHALE—Description—Range—Fishery—Incidents of the Chase—Habits—Harpooned—Treatment of the Carcass—SHORT-HEADEDWHALE,ORSNUB-NOSEDCACHALOT—DOLPHINS—CAAING,ORPILOTWHALE—RISSO’SGRAMPUS—COMMONPORPOISE—KILLERWHALE,ORORCA—Ferocity—TRUEDOLPHINS—COMMONDOLPHIN—BOTTLE-NOSEDOLPHIN—WHITEWHALE—NARWHAL—THE WHALEBONE WHALES—Whalebone—GREENLAND,ORRIGHTWHALE—BISCAYWHALE—JAPANWHALE—CAPEWHALE—SOUTHPACIFICWHALE—Description of the Greenland Whale—Their Food and Mode of Feeding—Habits—Hunting—Treatment of Carcass—HUMP-BACKEDWHALES—FINWHALES,ORRORQUALS—SIBBALD’SRORQUAL—SULPHUR-BOTTOMWHALE—COMMONRORQUAL,ORRAZOR-BACK—LESSERRORQUAL—Concluding Remarks.
Whales—Vulgar Notions—Characteristics External and Internal—Larynx—Tail—Skeleton—Classification—THE TOOTHED WHALES—ZEUGLODONS—SQUALODONS—PHOCODONS—RIVERDOLPHINS—SUSU,ORGANGETICDOLPHIN—Description—Habits—Teeth—INIA—PONTOPORIA—ZIPHIOIDWHALES—CUVIER’SWHALE—VANBENEDEN’SWHALE—SOWERBY’SWHALE—NEWZEALANDBERARDIUS—BOTTLEHEAD,ORCOMMONBEAKEDWHALE—SPERMWHALES,ORCACHALOTS—SPERMWHALE—Description—Range—Fishery—Incidents of the Chase—Habits—Harpooned—Treatment of the Carcass—SHORT-HEADEDWHALE,ORSNUB-NOSEDCACHALOT—DOLPHINS—CAAING,ORPILOTWHALE—RISSO’SGRAMPUS—COMMONPORPOISE—KILLERWHALE,ORORCA—Ferocity—TRUEDOLPHINS—COMMONDOLPHIN—BOTTLE-NOSEDOLPHIN—WHITEWHALE—NARWHAL—THE WHALEBONE WHALES—Whalebone—GREENLAND,ORRIGHTWHALE—BISCAYWHALE—JAPANWHALE—CAPEWHALE—SOUTHPACIFICWHALE—Description of the Greenland Whale—Their Food and Mode of Feeding—Habits—Hunting—Treatment of Carcass—HUMP-BACKEDWHALES—FINWHALES,ORRORQUALS—SIBBALD’SRORQUAL—SULPHUR-BOTTOMWHALE—COMMONRORQUAL,ORRAZOR-BACK—LESSERRORQUAL—Concluding Remarks.
STOMACH OF PILOT WHALE. (After Murie.)œ, œsophagus, or gullet;b, bile duct;i, intestine; 1, 1*, 2, 3, 4, represent the various chambers, the arrows denoting the direction food takes in passing onwards.
STOMACH OF PILOT WHALE. (After Murie.)
œ, œsophagus, or gullet;b, bile duct;i, intestine; 1, 1*, 2, 3, 4, represent the various chambers, the arrows denoting the direction food takes in passing onwards.
UPPER SURFACE OF THE BRAIN OF THE PORPOISE.(After Leuret and Gratiolet.)
UPPER SURFACE OF THE BRAIN OF THE PORPOISE.(After Leuret and Gratiolet.)
THEWhales form one of the most extraordinary groups of the Mammalia, for they are warm-blooded, air-breathers, and sucklers of their young, and are most strangely adapted for life in a watery element. Oddly enough the term “Fish” is still applied to them by the whalers, though they have nothing in common with these creatures save a certain similitude in shape. The vulgar notion of a Whale is an enormous creature with an extremely capacious mouth, but the fact is that many of the Cetacea are of relatively moderate dimensions, though doubtless, on the other hand, the magnitude of some is perfectly amazing. Thus, in size they are variable as a group, a range of from five or six feet (equal to the stature of man) to seventy or eighty feet giving sufficiently wide limits. With certain exceptions, notwithstanding length, an average-sized Whale by no means conveys to the eye the same idea of vastness, say for instance, as does an Elephant. The reason is that most Cetaceans are of a club shape, the compact cylindrical body and long narrow tapering tail reducing the idea of size. The head is in such continuity with the body that of neck there seems nothing. In some there are upright fleshy back fins; in others these are wanting. The gristly caudal fin is horizontal and not upright or rayed like a fish’s. The body is smooth and devoid of hair. The eye is remarkably small and without eyelashes, and the ear orifice is so diminutive as to seem deficient. The head is either rounded, massive, or has a long snout. There are no hind limbs, and only in the enormous Whalebone Whales have the rudiments of any been found. Small pelvic bones, however, are present, embedded in the flesh at the setting-on of the tail. The fore-limbs, which are ordinarily termed flippers, have the usual bones extremely broadened and flattened; the free part—equivalent to the hand—being encased in a rigid or stiff nailless membrane; and in a few instances the phalanges are exceedingly numerous, producing a long-fingered peculiarity met with in no other Mammal. The two mammæ adjoin the pelvic bones, the nipples being sunk in slits. In one section only, the Mysticete, is the mouth very large. In them great plates of the so-called whalebone, a horny substance, occupy the place of teeth. In another section, the Denticete, with moderate-sized mouth, teeth are present in few or greater numbers. These are implanted in simple sockets without successors—i.e., there is no milk and adult dentition as in the foregoing orders. The tongue cannot be thrustout. The gullet is narrow in some, and wider in others, but the stomach in all is peculiar, and composed of three or more chambers with narrow passages between; in this respect corresponding to that of Sheep and cattle. The intestines are long, glandular, and full of little pouches. There is no gall-bladder. The brain is of considerable calibre, globular, and remarkably convoluted. The heart is distinguished only for great size, and the blood-vessels are exceedingly capacious and numerous. But what is remarkable in the vascular system is a great mass composed of enormous numbers of minute tubes, forming a so-calledrete mirabile, like that formerly described in the Lemurs. It is situated within the body along the inside of the spine. This, in the Whales, has been supposed to be a respiratory provision to enable them to remain long submerged; but I have shown elsewhere that its connection with the glands of the lymphatic system may render it functionally subservient to nutrition and purification of the blood. The lungs are large, but the most extraordinary features are the larynx and nasal passages. The nostrils, often a single crescentic aperture, open right on the top of the head, except in the Sperm Whale, and not in front as in all other Mammalia. In some there are small pouches near the orifice or blowhole of uncertain use. In front of the larynx of man we all know there is an elastic lid, the epiglottis, which folds over and protects the passage as food is swallowed. The side cartilages constitute the walls of the organ of voice, and protect the vocal cords. Now, in the comparatively voiceless Whale the cartilages including the epiglottis form a long rigid cylindrical tube which is thrust up the passage at the back of the palate in continuity with the blowhole. It is there held in place by a muscular ring. With the larynx thus retained bolt upright, and the blowhole meanwhile being compressed or closed, the Cetacean is enabled to swallow food under water without the latter entering the lungs. Respiration, “blowing” or “spouting,” takes place at intervals as the animal reaches the surface, and the volume of air thrown up along with surrounding moisture and condensed vapour in some rises in a great jet. The flesh of the body terminates in long cords of tendon running to the tip of the tail. These tendons, like a telegraphic cable, bound together in the smallest compass, are moved by the enormous fleshy masses of the body, and thus their vast force is conveyed to the caudal appendage, whose great power as a propelling agent (and even a destructive one) enables the Whales to be truly roamers of the sea. Save the tail and flippers, the body is covered by a dense layer of fat, the blubber. In the skeleton the neck-bones are often soldered into one or two separate pieces, rigidity being needful in front, while theremaining vertebræ, tapering to exceedingly small bones in the tail, are each separated by thick elastic fibro-cartilaginous cushions, thus giving great flexibility behind. The breast-bone is often in a single flat piece. The skull is greatly modified and by no means uniform throughout the group. Among the Dolphins and others (Delphinidæ) it is strangely distorted, so that the one side does not agree with the other. The upper jaw-bones (maxillæ) and the pair of bones above and between them (premaxillæ) are unusually produced, and this production in front, with corresponding extension of lower jaw, gives a lengthened facial region and snout accordingly. The bones surrounding the occiput and brain-pan are directed upwards, the former occasionally forming a great horseshoe crest. The bony nasal passages instead of coming forward lead nearly direct upwards towards the summit of the cranium, nasal bones themselves being all but absent. The orbits are often small and open behind. Curiously enough, though deficient in ears, the interior tiny ear-bones of other Mammals are in the Whales great massive structures and exceedingly dense, so much so that they are frequently preserved fossil when other osseous structures are destroyed.
INTERIOR VIEW OF LARYNX OF RISSO’S GRAMPUS. (After Murie.)Ep, epiglottis;vc, vocal cord;s, sac;c, cartilage;gl, gland;tr, trachea. The arrows show direction of air-currents in ingress and egress.
INTERIOR VIEW OF LARYNX OF RISSO’S GRAMPUS. (After Murie.)
Ep, epiglottis;vc, vocal cord;s, sac;c, cartilage;gl, gland;tr, trachea. The arrows show direction of air-currents in ingress and egress.
SKELETON OF SPERM WHALE. (After Flower.)s, Spermaceti Cavity;n, Nasal Passage, in dotted line;b, Blowhole.
SKELETON OF SPERM WHALE. (After Flower.)s, Spermaceti Cavity;n, Nasal Passage, in dotted line;b, Blowhole.
Cetacea have been a troublesome group to unravel, being ocean-dwellers, and many of them huge brutes. To study them in the live state has been difficult, and their carcases when captured or stranded on shore are as unmanageable for purposes of examination. As to their classification the two sub-orders—Denticete, Toothed Whales, and Mysticete, Whalebone Whales—are universally accepted. As regards the families, the main groups are tolerably well agreed upon, though differently named by authorities. Among the sub-families, the genera and the species, there is less unanimity. The grouping of the living forms proposed by Professor Flower is in Great Britain more frequently adopted, while MM. Gervais and Van Beneden, in their great work on “Osteographie des Cétacés,” have collated the living and fossil forms. Some species and genera of Whales are restricted within given areas, as are the Seals, but of the habitat of many others in truth so little is known that no defined limit can be assigned. The great majority are migratory; some are gregarious, others more solitary in disposition. A few are quite fluviatile; but most are found in the high seas. Following the above primary divisions, we give precedence to