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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 Stocks and Shares; Company; and Debentures). From the same O. Eng. verb sceran is derived “ share ” (O. Eng. scear), the cutting blade of a plough (q.v.).

SHARI, an important river of North-Central Africa, carrying the drainage of a large area into Lake Chad (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 Wam flows east and then north and in about 7° 20′ N., 18° 20′ E. is joined by the Fafa, a considerable stream rising east of the Wam. The upper course of the Wam is much obstructed by rapids, but from a little above the Fafa confluence it becomes navigable. Below the confluence the river, now known as the Bahr Sara, receives three tributaries from the west. In about 9° 20′ N., 18° E., it is joined by the Bamingi, which is formed by the junction of the eastern head streams of the Shari. The Bamingi, before the exploration of the Wam, was thought to be the true upper course of the Shari. One of its branches, the Kukuru, rises in about 7° N., 21° 15′ E. Some 90 m. from its source the Bamingi becomes navigable, being 12 ft. deep and flowing with a gentle current. In 8° 42′ N. it receives on the west bank the Gribingi, a river rising in about 6° 20′ N. It is narrow and tortuous with rocky banks and often broken by rapids, but navigable at high water to 7° N. It flows in great part through a forest-clad country. A few miles above its confluence with the Bahr Sara the Bamingi receives on the right hand another large river, the Bangoran, which rises in about 7° 45′ N. and 22° E., in a range of hills which separates the countries of Dar Runga and Dar Banda, and, like the Bamingi, flows through open or bush-covered plains with isolated granite ridges.

Below the junction of the Bahr Sara and the Bamingi the Shari, as it is now called, becomes a large river, reaching, in places, a width of over 4 m. in the rains; while its valley, bordered by elevated tree-clad banks, contains many temporary lakes and back-waters. Its waters abound with hippopotami and crocodiles, and the country on either side with game of all kinds. In 9° 46′ N. it receives the Bakare or Awauk (Aouk) from the east, known in its upper course as the Aukadebbe. This, like the Bahr es Salamat, which enters the Shari in 10° 2′ N., traverses, a wide extent of arid country in southern Wadai, and brings no large amount of water to the Shari. In 10° 12′ a divergent branch, the Ergig, leaves the main stream, only to rejoin it in 11° 30′.

In 12° 15′ N. and 15° E. the Shari receives on the west bank its largest tributary, the Logone, the upper branches of which rise far to the south between 6° and 7° N. The principal head streams are the Pende and the Mambere. The Pende rises some 30 m. N. by E. of the source of the Wam. It flows northwards through a fertile valley and in 9° 35′ N. and 16° E. is joined by the Mambere, which rises in the hills of Adamawa and flows in a course roughly parallel to the Pende. Below the junction of the Pende and Mambere the Logone is a broad and deep river. Its system is connected with that of the Benue (see Niger) by the Tuburi Swamp, which sends northward a channel joining the Logone in about 10° 30′ N. Below the Logone confluence the Shari, here a noble stream, soon splits up into various arms, forming an alluvial delta, Hooded at high water, before entering Lake Chad. From the source of the Wam to the mouth of the river is a distance, following the windings of the stream, of fully 1400 m.

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 Chad). 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 Niger.)

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.

See the works of Barth, Nachtigal and other travellers, especially Lenfant’s La Découverte des grander sources du centre de Afrique (Paris, 1909).

SHARK, a Selachian fish (see Selachians), 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.,

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

Fig. 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