Marsh, Adam, or Adam de Marisco, d. 1259?, English Franciscan scholar. He was a student of Robert Grosseteste. When Grosseteste became bishop, Marsh took his place in the Franciscan school at Oxford. Marsh's advice and his services as a peacemaker were constantly sought, and Grosseteste relied heavily on him. Actively supporting the reform party of Simon de Montfort (1208?-1265), Marsh was able nevertheless to retain the confidence of Henry III. Of his writings only his letters survive.

Marsh, Dame Ngaio, 1899-1982, New Zealand detective story writer. She was an art student, actress, and theatrical producer before her first novel, A Man Lay Dead, was published in 1934. Her many mystery novels, acute in characterization and literate in style, reflect her knowledge of the art studio and the theater. They include Artists in Crime (1938), Died in the Wool (1945), False Scent (1959), Killer Dolphin (1966), Last Ditch (1978), Photo Finish (1980), and her last book, Light Thickens, published posthumously (1982). She was made a Dame of the British Empire in 1966.

Marsh, Reginald, 1898-1954, American painter and illustrator, b. Paris. Both his parents were artists. After their return to the United States, he studied at Yale (B.A., 1920). He worked as an illustrator for Vanity Fair, Harper's Bazaar, and the New York Daily News, and later he was a scene designer. He then studied under John Sloan and K. H. Miller at the Art Students League. From 1925 to 1939 he made two trips to Europe and sketched for the New Yorker. His lively recordings of Manhattan street life in many media were popular. "Why Not Use the ‘L’?" (1930; Whitney Mus., New York City) is typical. Marsh painted two celebrated murals in the Post Office Building, Washington, D.C.

marsh: see swamp.

Perennial herbaceous plant (Caltha palustris) of the buttercup family, native to wetlands in Europe and North America. It is grown in boggy wild gardens. The plant has a hollow stem, heart-shaped or round leaves, and glossy pink, white, or yellow flowers composed solely of sepals (petals are absent). The stems, leaves, and roots are sometimes cooked and eaten as a vegetable, though the fresh plant is poisonous. Seealso cowslip.

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Perennial herbaceous plant (Althaea officinalis) of the mallow family, native to eastern Europe and northern Africa and naturalized in North America. Found usually in marshy areas near the sea, the marsh mallow has strongly veined, heart-shaped or oval leaves and pinkish flowers borne on stalks about 6 ft (1.8 m) tall. The root was formerly processed to make marshmallows.

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or marsh gas

Organic compound, chemical formula CH₄, colourless, odourless gas that occurs in natural gas (called firedamp in coal mines) and from bacterial decomposition of vegetation in the absence of oxygen (including in the rumens of cattle and other ruminants and in the gut of termites). The simplest member of the paraffin hydrocarbons, methane burns readily, forming carbon dioxide and water if supplied with enough oxygen for complete combustion or carbon monoxide if the oxygen is insufficient. Mixtures of 5–14percnt methane in air are explosive and have caused many mine disasters. The chief source of methane is natural gas, but it can also be produced from coal. Abundant, cheap, and clean, methane is used widely as a fuel in homes, commercial establishments, and factories; as a safety measure, it is mixed with trace amounts of an odorant to allow its detection. It is also a raw material for many industrial materials, including fertilizers, explosives, chloroform, carbon tetrachloride, and carbon black, and is the principal source of methanol.

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Freshwater or marine wetland ecosystem characterized by poorly drained mineral soils and by plant life dominated by grasses. Fewer plant species grow in marshes than on well-watered but not waterlogged land; grasses, sedges, and reeds or rushes are most common. Commercially, rice is by far the most important freshwater marsh plant: it supplies a major portion of the world's grain. Salt marshes are formed on intertidal land by seawater flooding and draining, and salt-marsh grasses will not grow on permanently flooded flats. Seealso swamp.

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(born March 14, 1898, Paris, France—died July 3, 1954, Bennington, Vt., U.S.) U.S. painter and printmaker. Born to American parents in Paris and educated at Yale University, from 1922 to 1925 he produced a daily column of drawings of vaudeville acts for the New York Daily News. In 1925 he became an original member of the staff of The New Yorker magazine, for which he drew humorous illustrations and metropolitan scenes. In 1929 he began painting scenes of city life, including Coney Island crowds and Bowery derelicts. He taught at the Art Students League from 1934 until his death.

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(born March 14, 1898, Paris, France—died July 3, 1954, Bennington, Vt., U.S.) U.S. painter and printmaker. Born to American parents in Paris and educated at Yale University, from 1922 to 1925 he produced a daily column of drawings of vaudeville acts for the New York Daily News. In 1925 he became an original member of the staff of The New Yorker magazine, for which he drew humorous illustrations and metropolitan scenes. In 1929 he began painting scenes of city life, including Coney Island crowds and Bowery derelicts. He taught at the Art Students League from 1934 until his death.

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In geography, a marsh, or morass, is a type of wetland which is subject to frequent or continuous inundation. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, and other herbaceous plants. Woody plants will be low-growing shrubs. A marsh is different from a swamp, which has a greater proportion of open water surface and may be deeper than a marsh. In North America, the term swamp is used for wetland dominated by trees rather than grasses and low herbs.

The water of a marsh can be fresh, brackish, or saline. Coastal marshes may be associated with estuaries, and are also along waterways between coastal barrier islands and the inner coast. The estuarine marsh, or tidal marsh, is often based on soils consisting of sandy bottoms or bay muds. An example is the Tantramar Marsh of eastern Canada.

Marshes are critically important wildlife habitat, often serving as breeding grounds for a wide variety of animal life, particularly including ducks and geese.

Constructed wetlands featuring surface-flow design are usually in the form of a marsh.

Decomposition of plant materials below water often produces marsh gas, which may begin to burn by self-ignition making mysterious lights known locally as Will o' the wisps, Jack-a-lanterns, or sprites.

See also

Aquatic plant Bayou Biodiversity Action Plan Bog Fen		Mesopotamian Marshes Salt marsh Swamp Will-o'-the-wisp

Chassidy

Reference line notes

• Marshes of the Lowcountry (South Carolina) -- Beaufort County Library
• General Information of Ibera Marshes (in English and Spanish)