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Rh number of persons. The word is particularly applied to the fixed and equal amounts into which the capital of a limited company is divided (see ; ; and ). From the same O. Eng. verb sceran is derived “ share ” (O. Eng. scear), the cutting blade of a (q.v.).

 SHARI, an important river of North-Central Africa, carrying the drainage of a large area into (q.v.). Its head streams rise on the watersheds between the Lake Chad basin and those of the Nile and Congo. The principal head stream, known variously as the Wahme, Wa, Wam or Wom, rises, in about 6° 30′ N., 15° E., in mountainous country forming the divide between the Chad system and the basin of the Sanga affluent of the Congo.

The existence of the Shari was made known by Oudney, Denham and Clapperton, the first Europeans to reach Lake Chad (1823). In 1852 Heinrich Barth spent some time-in the region of the lower Shari and Logone, and in 1872–1873 Gustav Nachtigal studied their hydro graphical system and explored the Gribingi, which he called the Bahr el Ardhe. It was not, however, until the partition of the Chad basin between Great Britain, France and Germany (1885–1890) that the systematic exploration of the Shari and its affluents was undertaken. The most prominent explorers have been Frenchmen. In 1896 Émile Gentil reached the Bamingi and in a small steamer passed down the river to its mouth. The existence of the Bahr Sara had been made known by C. Maistre in 1892, and in 1894 F. J. Clozel discovered the Wam. In 1900 A. Bernard demonstrated the identity of these two streams. In 1907 an expedition under Captain E. Lenfant followed the Wam-Bahr Sara from its source to the confluence with the Bamingi and showed it to be the true upper course of the Shari. The same expedition also discovered the Pende tributary of the Logone. Captain Lenfant had previously demonstrated (1903) the Connexion between the Benue and Logone. From the mouth of the Shari in Lake Chad there is a current towards the Bahr-el-Ghazal channel at the south-eastern end of that lake. This channel has been supposed to be a dried-up affluent of the lake (see ). Investigations by the French scientists E. F. Gautier and R. Chudeau led Chudeau to the conclusion that the Shari did not end in Lake Chad, but, by way of the Bahr-el-Ghazal, passed between Tibesti and Ennedi and ended in some shat in the Libyan desert. That the Shari may have reached the Nile is an hypothesis not absolutely rejected. (See Missions au Sahara, tome ii. (Paris, 1909), and for theories as to the Niger-Nile connexion see .)

From the spot where it is intersected by 10° 40′ N. to Lake Chad the Shari forms the boundary between the German colony of Cameroon and French Congo. The best route from the Congo to Lake Chadis via the Sanga affluent of the Congo to the station of Carnot, and thence across the watershed to the Pende.

SHARK, a Selachian fish (see ), belonging to the order Plagiostomi, suborder Squali.

Sharks are almost exclusively inhabitants of the sea, but some species enter the mouths of large rivers, and one species (Carcharias gangeticus) occurs frequently high up in the large rivers of India. C. nicaraguensis of the lake of Nicaragua and the Rio San Juan appears to have taken up its residence permanently in fresh water. Sharks are most numerous between the tropics, a few only reaching the Arctic circle; it is not known how far they advance S. in the Antarctic region. Altogether some hundred and fifty different species have been described. With regard to their habits many are littoral species, the majority pelagic, and a few are known to belong to the deep-sea fauna, having hitherto been obtained down to a depth of nearly 1000 fathoms.

Littoral Sharks.—The littoral forms are of small size, and generally known under the name of “dog-fishes,” “hounds,” &c. Some pelagic sharks of larger size also live near the shore on certain parts of. a coast, but they are attracted to it by the abundance of food, and are as frequently found in the open sea, which is their birthplace; therefore we shall refer to them when we speak of the pelagic kinds.

The majority of the littoral species live on the bottom, sometimes close inshore, and feed on small marine animals or on any animal substance. The following are deserving of special notice.

The tope (Galeus) is common on the coasts not only of England, Ireland and of S. Europe, but also of S. Africa, California, Tasmania and New Zealand. Its teeth are equal in both jaws, of rather small size, flat, triangular, with the point directed towards the one side, and with a notch and denticulations on the shorter side (fig. 1). It is of a uniform 1 slaty-grey colour, and attains to a length of 6 ft. The female brings forth some thirty living young at one birth in May. It becomes troublesome at times to fishermen by taking their bait and driving away other fish they desire to catch. The fins of G. zyopterus of the Californian coast are much esteemed for culi- nary purposes by the Chinese.,

. 1.—Teeth of Tope. u, Upper; l, lower.

. 2.—Teeth of Mustelus.

The hounds proper (Mustelus) possess a very different dentition, the teeth being small, obtuse, numerous, arranged in several rows like pavement (fig. 2). Five or six species are known from the shores of the various temperate and subtropical seas, one (M. vulgaris) being common on the coasts of Great Britain and the United States, on the Pacific as well as the Atlantic side. It is of a uniform grey colour or sparingly spotted with white, and attains to a length of 3 or