ARRONDISSEMENT (from Fr. arrondir, to make round), in France, an administrative subdivision of a department. It com prises within itself the canton and the commune. It is merely an administrative division and not a complete legal personality with power to acquire and possess. It is the electoral district for the chamber of deputies, and is a judicial district having a court of first instance. It is under the control of a sub-prefect. There are 362 arrondissements in the 87 departments. Each arrondissement has a council, with as many members as there are cantons, whose function is to subdivide among the corn munes their quota of the direct taxes charged to the arrondisse ment by the general council of the department. (See FRANCE.) The cities of Paris and Lyons are divided into local administrative units also termed arrondissements.
France is also subdivided, for purposes of defence, into five maritime divisions, termed arrondissements. They are under the direction of maritime prefects, who, by a decree of 1875, must be vice-admirals in the navy.
(S a g i t taria), a group of perennial aquatic or marsh herbs of the water-plantain family (Alisma ceae), so named because the leaves of the best known species are characteristically arrow-shaped. The scapes, which rise from tuber bearing or fleshy knotted root stocks, are mostly erect though sometimes decumbent and more rarely floating. Though borne on partly submerged stalks, the strongly nerved leaves usually rise conspicuously above the water. The flowers, arranged in whorls of three at the top of the scapes, have three broad white petals alternating with three small green sepals ; the fruit is a dense head of small achenes. There are about 3o species, native to temperate and tropical regions, but chiefly American. The common Old-World arrow-head (S. sagit ti f olia) , found in ditches in England and Ireland, is very widely distributed in Europe and Asia. It grows aft. to Oft. high and bears showy white flowers and orbicular achenes. Many profusely blooming and double-flowered varieties are cultivated in lily ponds and bog gardens. The similar broad-leaved arrow-head (S. lati f olia), with sharply beaked achenes, grows in shallow water throughout North America except in the Arctic region. Its large starchy tubers, called wappato, are used for food by the American Indians. In the lower San Joaquin and Sacramento valleys in California this arrow-head is known as "tule potato," and is often cultivated for food by the Chinese of the district in a manner similar to the cultivation for its starchy tubers of S. chinensis in China. The giant arrow-head (S. montevidensis) sometimes grows 6ft. tall, with leaf blades eft. long, and bears showy white flowers from tin. to Sin. across, blotched with brownish-purple at the base. This handsome species is native in South America from Peru and Chile to Brazil and Argentina, and was first introduced into cultivation in 1883 from seeds sent to England from Buenos Aires. It is now planted in water gardens in the warmer parts of the United States and has run wild in slow streams in California and the south Atlantic States.