Catha. Catha edulis.—Under various Arabic names, such as Kat, Khat, Chaat, Kus es Salahin, Tchaad, Tschut, Tohat, Tohai, Gat, the leaves of Catha edulis Forsk. (fam. Celastracae) (Abyssinian or African tea) are very largely used as a stimulant in Northern Africa, the plant being extensively cultivated. According to Collin, from 1400 to 1500 camel loads are yearly sold in Aden. The plant is a shrub, reaching the height of 9 to 12' feet, with thin coriaceous leaves whose margins are bluntly serrate. The rounded grayish-green twigs are, for commercial purposes, dried with the leaves and tied together in bundles containing about forty twigs; the bundles are commonly from twelve to fourteen inches in length and three to four inches in diameter, but sometimes much smaller. The leaves are chewed both in the green and fresh condition, and are in some places made into a tea. The taste is sweetish and astringent, somewhat suggesting licorice. They are asserted to act as stimulants, overcoming the sense of fatigue in the same way as cocaine, or caffeine. Flückiger and Gerrock found in it an alkaloid, ratine, C10H18ON2, which has been studied by Chevalier (B. G. T., 1911), who finds that it is a stimulant to the central nervous system. Stockman (P. J., Nov. 30, 1912) found three alkaloids, cathine, cathinine, and cathidine, and also a fourth alkaloid in too small quantities for study. He found (J. P. Ex. T., 1913, iv) that these alkaloids were stimulating to both the brain and spinal cord, and in large doses produced paralysis through a direct action upon the muscle.