ACER, a name given by the Romans to a tree called Maple by the English. It is now applied to a genus of arborescent or shrubby plants, many of which are extremely valuable for the sake either of their timber or of their ornamental appearance. It is the type of the natural order A ceracem. It has the following characters :—Flowers green and inconspicuous, either containing stamens only, or pistils only, or both united, upon the same individual. Calyx divided into five lobes, of uncertain length. Stamens occasionally five ; more fre quently varying from seven to nine. Leaves in all cases simple. Fruit double ; each division containing one single-seeded cavity, and extended at the back into a kind of wing, called Key in English, or Samara by botanists.
1. Acer oblangum, Oval-Leafed Maple, an evergreen tree, of rapid growth, native of the northern parts of India, both in Nepaul and Knmaon. It is probably confined to the hot valleys of those regions, for it has been found incapable of supporting the climate of England.
2. lmrigatum (Wallich), the Polished Maple. Leaves oblong, taper-pointed, slightly serrated, shining, green beneath. Flowers white, in branched erect thyrses. Keys broad, short, smooth. It is found in the woods of the higher mountains of Nepaul, and also in the Alps of Sit-moor, where it acquires a trunk thirty or forty feet high, and from three to four feet thick. Its growth is slow ; its timber is said by Dr. Wallich to be used by the inhabitants of Nepaul for rafters, beams, and similar building purposes.
3. Acer Tataricunt (Linnaeus), the Tartarian Maple. Leaves heart shaped, oblong, unequally serrated, usually undivided. It forms an ornamental tree, or rather large bush, from fifteen to twenty feet high, often met with in gardens and plantations. Its native countries are the southern provinces of Russia in Asia, whence it extends as far as Ilungary, there finding its most western limit. From its keys, deprived of their wings, the Cahnues form, by the aid of boiling water, an astringent beverage, which, mixed with an abundance of milk and butter, forms a favourite article of their diet. The wood in hard and white, mixed with brownish veins.
4. Acer striatum, the Striped-Bark Maple (A. Pennsylranicum, Linnrcus). Loaves roundish, finely serrated, divided at the upper end into three nearly equal tapering lobcs, ; when young, covered with a meanness, which is gradually thrown off as they increase in size. It
is a native of North America, from Canada to the high lands in Georgia. In those countries it forms a considerable part of the undergrowth of the woods, among sugar-maples, beeches, birches, and hemlock-spruce firs. It rarely exceeds eight or ten feet in height, except in a very few favonrable situations, when it will occasionallygrow double that height. Its wood in very white, and is used by the North Americans for inlay 5. A cer barbaturn (Michaux), the Bearded Maple. Leaves heart shaped, three-lobed, nearly equally serrated ; the lobes of nearly equal size, or the lateral ones much the smallest ; nearly smooth beneath. It is a native of deep pine and cedar swamps in Jersey and Carolina, where its forms a small tree.
6. Acer spicat um, the Spike-Flowered Maple (A. montanum, Aiton). Leaves heart-shaped, smooth above, downy and glaucous beneath, of an oblong figure, with about five unequal, tapering, coarsely and unequally serrated divisions. It is a native of the United States and Canada. The red colour of its keys in the autumn forme its principal beauty.
7. Acer opulus (Aiton), the Gueldres-Rose-Leaved Maple. Leaves more or less heart-shaped, roundish, five-lobed, smooth beneath. It is a small tree, ten or twelve feet high, found in France, especially in Dauphiny.
8. Acer obtusat um. (Willdenow), the Neapolitan Maple. Leaves heart-shaped, roundish, five-lobed, woolly beneath ; the lobes either obtuse or pointed, and coarsely serrated. Flowers in drooping corymbe. Hungary, Croatia, and many parts of Italy, produce this beautiful species. On all the hills and lower mountains of the kingdom of Naples, in Camaldoni, Castellamare, and the Abruzzi, it is found abundantly, growing usually to the height of forty feet ; it is extremely striking, with its reddish-purple branches, in the wood of Lucania, between Rotonda and Rubia ; and in the Basilicata and Calabria it is said, by Tenore, to acquire colossal dimensions. It is certainly very singular that so fine a tree as this, occupying so large a tract of country, frequently visited by English tourists, should be almost unknown in this country; and yet, although it is perfectly hardy, and very easily multiplied, it is scarcely ever met with in any but botanical collections. There are two forms of the leaf—one with blunt, and the other with pointed lobes.