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ALOE, a genus of plants belonging to the family Liliaceae, with about 18o species growing in the dry parts of Africa, espe cially Cape Colony, and in the mountains of tropical Africa. Members of the closely allied genera Gasteria and Haworthia, with a similar mode of growth, are also cultivated and popularly known as aloes. The plants are apparently stemless, bearing a rosette of large, thick, fleshy leaves, or have a shorter or longer (sometimes branched) stem, along which, or towards the end of which and its branches, the generally fleshy leaves are borne. They are much cultivated as ornamental plants, especially in public buildings and gardens, for their stiff, rugged habit. The leaves are generally lance-shaped with a sharp apex and a spiny margin; but vary in colour from grey to bright green, and are sometimes striped or mottled. The rather small tubular yellow or red flowers are borne on simple or branched leafless stems, and are generally densely clustered. The juice of the leaves of certain species yields aloes. In some cases, as in Aloe venenosa, the juice is poisonous. The American aloe, Agave americana (see AGAVE), belongs to a different family, viz., Amaryllidaceae.

Aloes is a medicinal substance used as a purgative and produced from various species of aloe, such as A. vera, vulgaris, socotrina, chinensis, and Perryi. Several kinds of aloes are distinguished in commerce--Barbadoes, Socotrine, hepatic, Indian, and Cape aloes. The first two are those commonly used for medicinal purposes. Aloes is the expressed juice of the leaves of the plant. When the leaves are cut the juice flows out, and is collected and evaporated. From the juice active principles termed aloins are extracted by - water.

The lign-aloes is quite different from the medicinal aloes. The word is used in the Bible (Numb. xxiv. 6), but as the trees usually supposed to be meant by this word are not native in Syria, it has been suggested that the LXX. reading in which the word does not occur is to be preferred. Lign-aloe is a corruption of the Lat. lignum-aloe, a wood, not a resin. Dioscorides refers to it as agallo chon, a wood brought from Arabia or India, which was odoriferous but with an astringent and bitter taste. This may be Aquilaria Agallocha, a native of East India and China, which supplies the so-called eagle-wood or aloes-wood, which contains much resin and oil.

aloes, leaves, juice and plants