Page:The American Cyclopædia (1879) Volume XIV.djvu/853

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SHARK 827 four or five small points on each side; the parts about the mouth and nose in some gen- era are divided into flaps and barbels, evident- ly organs of touch, necessary in their rapid passage along the bottom. They are ovipa- rous, and the eggs resemble those of a skate. In the genus scylUum (Mull, and Henle) the spiracles are close behind the eyes, and the nostrils near the mouth and valved ; dermal scales tricuspid. Most of the species are found around the southern coasts of Africa; they are among the smallest of the sharks, and live near the ground. There are two species on the English coast, the 8. catulus (Cuv.) and S. ca- nicula (Cuv.). The former is 2 or 3 ft. long, brownish gray above, with a few large black- ish and white spots, and whitish below; the food consists of fish, mollusks, and crustaceans ; it deposits about 20 eggs, according to Cu- vier. The latter, the small spotted dog fish, about 2 ft. long, is more reddish, with more numerous and smaller spots ; it is widely dis- tributed, following ships and seizing whatever falls overboard; it eats chiefly fish, but has been known to attack fishermen and bathers ; it lies in ambush in the mud or among weeds. Both these species are the pests of the fishing stations all along the coast, especially among the Orkney islands, robbing the lines at every opportunity, and not unfrequently caught themselves; the flesh is white, but dry and fibrous, and, though eaten by the fishermen, is rarely brought to market ; in the Orkneys they are skinned, split, and dried ; the skin is used by cabinet makers as a fine rasp, and the liver is valuable for its oil. Among the genera and species of N. E. Asia are many whose fins are used for soups by the Chinese. Under the name of squali Cuvier compre- hended all the other sharks, except the ham- mer-head and monk fish, of which he made distinct genera ; Owen gives the name of nic- titantes to a portion of the squali, chiefly car- chariadce and galeidce (described below), the presence of a nictitating membrane to the eye being accompanied with a greater induration of the skeleton. In the family carchariadce there are two dorsals and an anal, the first dorsal over the space between the pectorals and ventrals ; there are no spiracles, and the last two gill openings are over the pectorals; nostrils generally small, pupil perpendicularly oval, and mouth boldly convex ; the teeth are compressed, triangular, with an entire or ser- rated edge, arranged in a linear series like those of a saw, in several rows, of which the anterior only are erected for use ; the tail has a short under lobe and a notch near the end of the upper ; there is a pit above and below the base of the tail; the intestinal valve is longitudinally and not spirally rolled; skin comparatively smooth. The genus carcharia* (Mull, and Henle) has been divided into various subgenera, but all have the nostrils midway between the mouth and end of the flattened snout, the labial cartilages very small, and the yolk bag connected with a kind of uterine pla- centa in the smooth or villous oviduct. The white shark (C. vulgaru, Cuv.) attains a length of 30 to 35 ft., and a weight of more than 2,000 Ibs. ; the color is ashy brown above and whitish below; the head is large, the gape White Shark (Carcharias vulgaris). enormous, and the body stout; the teeth form such a perfect cutting apparatus, that the body of a man may be cleanly divided at a single bite ; some of the jaws of this species (which are not the true jaw bones, however) are large enough, even when shrunk by drying, to slip over the body of a man ; it has been seen near Calcutta to swallow a bullock's head and horns entire. This is the man-eater shark about which so many stories have been circulated, and hu- man remains have been found in its stomach ; it is gluttonous, savage, and bold ; its ordinary food consists of large fish, seals, cuttle fishes, and decaying animal matters. It is found in almost all oceans, though most abundantly in tropical waters, and is a rapid and surface swimmer ; it occasionally makes its appear- ance in the Mediterranean and on the British coasts. It is the terror of sailors, who always kill it when possible; as it follows ships to feed upon the garbage thrown overboard, and bites eagerly at any large bait dragging at the stern, it is not unfrequently caught, the pre- caution being taken to cut off the tail as soon as it is brought on board in order to prevent injury from its blows. The sense of hearing is very fine, if we can judge from the large size of the semicircular canals and vestibule of the ears. The young are born alive at different periods, until 20 or 30 are produced ; they are 7 or 8 in. long at birth. This species meets with a formidable enemy in the sperm whale, and is often destroyed by it after a long and bloody combat ; like all sharks, it is greatly in- fested with intestinal worms. The blue shark (C. glaucus, Cuv.) is a smaller species, rarely more than 8 ft. long ; it is more slender and