CORNALES

the dogwood order of flowering plants, belonging to the class Magnoliopsida (dicotyledons; characterized by two seed leaves). The order has 3 familiesCornaceae (dogwood), Alangiaceae, and Garryaceaeand fewer than 150 species. The largest family, Cornaceae (some 100 species), is only a loose grouping, and 11 of its 14 genera have been placed in single families by some authorities. The Cornales are, with few exceptions, woody plants. The flowers usually have parts in multiples of four; petals, when present, are usually distinct. The ovary is inferior and contains several carpels; there are as many locules and ovules as carpels. The fruits are fleshy and remain closed at maturity (indehiscent). The order is believed to be derived from the Rosales. Diversification of the order into families and genera was well under way by the Late Cretaceous Period (97.5 to 66.4 million years ago). The Garryaceae, which have the most reduced flowers in the order, are found in the fossil record beginning in the Miocene Epoch (from 23.7 to 5.3 million years ago). Dogwood (Cornus florida) The Cornaceae, or dogwood family, is distributed in temperate and warm temperate zones and on tropical mountains. The family is noted for its woody ornamental species that are native to both coasts of North America and to eastern Asia. Some of its members, such as the flowering dogwood (Cornus florida; see photograph) and the Japanese laurel (Aucuba japonica), are chiefly ornamental; the European Cornus mas (cornelian cherry), also an ornamental, has edible fruit; others, such as Cornus macrophylla and representatives of Curtisia, yield wood for furniture. In the flowering dogwoods, flowers are small and the conspicuously expanded structures are coloured bracts (specialized leaves) that surround the cluster of true flowers. The family Alangiaceae has only one genus, Alangium, with some 17 species. They are native to eastern and tropical Asia, eastern Australia, the Pacific islands, Madagascar, and western Africa. Species of Alangium are cultivated as ornamentals. Garryaceae also contains only one genus, Garrya; the family has 13 species. These are found in western North America and in Central America; one species is found in the Greater Antilles. Members of the family produce highly toxic alkaloids. Several species are planted as ornamentals.