stone marten: see marten.

pine marten: see marten.

marten, name for carnivorous, largely arboreal mammals (genus Martes) of the weasel family, widely distributed in North America, Europe, and central Asia. Martens are larger, heavier-bodied animals than weasels, with thick fur and bushy tails. Members of most species are brown above and light-colored below. The American marten, Martes americana, also called American pine marten and American, or Hudson Bay, sable, is from 20 to 25 in. (51-64 cm) long, including the 7- to 8-in. (18- to 20-cm) tail, and has yellow-brown fur. It lives in coniferous forests from Alaska to the extreme N United States, extending south in western mountain ranges. It is mostly nocturnal and spends much of the time in trees, where it leaps from branch to branch, although it also forages on the ground; it makes its den in a hollow tree or log. Its diet consists chiefly of small animals, especially red squirrels (Tamiasciurus), but it also eats berries and nuts. The other North American species, M. pennanti, is called fisher; both are valued for their fur. Similar to the American marten are the European pine marten, M. martes, and the stone, or beech, marten, M. foina, of Europe and central Asia. The stone marten is grayish. The Siberian sable, M. zibellina, is a marten species that produces extremely valuable fur. The yellow-throated martens, M. flavigula of E Asia and M. gwatkinsi of S Asia, are patterned in shades of brown, yellow, and orange. Martens are classified in the phylum Chordata, subphylum Vertebrata, class Mammalia, order Carnivora, family Mustelidae.

Vos, Marten de, c.1536-1603, Flemish painter. He studied with Floris in Antwerp and is said to have assisted Tintoretto in Venice. In 1558 he returned to Antwerp after seven years in Italy. Vos was a mannerist and painted chiefly ambitious figure compositions in imitation of the Venetians. Characteristic are his Temptation of St. Anthony and Triumph of Christ (Antwerp). Much of his work in the churches of Antwerp was destroyed by the iconoclasts.

Any of several forest-dwelling carnivore species (genus Martes, family Mustelidae). Species differ in size and colour, but they resemble weasels in general proportions, and their fur is valuable. Their total length is 20–40 in. (50–100 cm), and they may weigh 2–5 lb (1–2.5 kg) or more. Martens hunt alone, feeding on animals, fruit, and carrion. The fur of the American marten (M. americana) of northern North America is sometimes sold as sable. Other species include the pine, baum, or sweet marten (M. martes) of Europe and Central Asia and the yellow-throated marten, or honey dog (M. flavigula), named for its preference for sweet foods, of southern Asia. Seealso fisher; polecat.

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Rare species of marten (Martes pennanti, family Mustelidae) found in northern forests of North America. The fisher is related to weasels and is similarly shaped. It has a bushy tail, tapered muzzle and low, rounded ears. Adults are usually 20–25 in. (50–63 cm) long, excluding the 13–17-in. (33–43-cm) tail, and weigh 3–15 lb (1.4–6.8 kg). Fishers hunt on the ground and in trees, attacking various rodents and other animals; they also eat fruits and sometimes nuts. It has been trapped for its valuable brownish black fur.

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(born Feb. 17, 1890, East Finchley, Middlesex, Eng.—died July 29, 1962, Adelaide, S.Aus., Austl.) British statistician and geneticist. As statistician for an agricultural research institute, he investigated the linkage of genes for different traits. To avoid unintentional bias in selection of materials used in experiments, he introduced the principle of randomization. It states that before an experimental effect can be attributed to a given cause or treatment, the experiment must be repeated on control units of the material and that all material used in experiments must be selected at random from the whole population it intends to represent. He also developed the concept of the analysis of variance, a statistical procedure used to design experiments that answer several questions at once.

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(born Feb. 27, 1867, Saugerties, N.Y., U.S.—died April 29, 1947, New Haven, Conn.) U.S. economist best known for his work in the field of capital theory. He received his Ph.D. from Yale University. As a professor at Yale (1892–1935), he examined the relationship between changes in the quantity of money and the general level of prices. He also promoted the concept of the “compensated dollar”—a dollar of constant purchasing power, defined in terms of an index of commodity prices rather than in terms of a given weight of gold. Seealso price index.

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(born April 9, 1758, Dedham, Mass.—died July 4, 1808, Dedham, Mass., U.S.) U.S. essayist and Federalist politician. He graduated from Harvard College in 1774 and taught school for five years before turning to the law; he was admitted to the bar in 1781. Supporting the creation of a strong central government, Ames argued for ratification of the new U.S. Constitution at the Massachusetts constitutional convention. He became known for his uncompromising advocacy of the rights of property and his protective attitude toward commercial interests, which he defended in trenchant writing and commanding speech. In 1788 he defeated Samuel Adams for a seat in the first session of the U.S. House of Representatives; he was reelected three times. His eloquent support of the treaty negotiated by John Jay to preserve peace with England (1794) convinced the House to pass an enabling appropriation.

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