ARACHIS, a genus of plants of the natural order leguminosce, sub-order papitionacece, natives of the warm parts of America, of which, until recently, the only known species was the A. hypogcect, sometimes called the underground kidney-bean, and more frequently the ground-nut. It also receives the names of earth-nut, American earth-nut, and man dubi. It is an annual plant, with hairy pinnate leaves, which have four leaflets. The flowers are yellow, the standard veined with red. After flowering, the flower-stalks elongate and bend towards the earth, into which the pods penetrate, ripening under ground. The pods have a lining of a sort of network, and generally contain two, three, or four seeds, which are about the size of a hazel-nut, of a sweet taste, with a little of the flavor which belongs to most kinds of pulse. This plant is now cultivated in all the warm regions of the globe, and its usefulness is such that its cultivation is likely to extend. It was introduced from Peru into Spain, and thence into France. It succeeds favorable situations even in the middle of France, where it is sown after all danger of frost is thought to hoover, and yields from eighty to a, hundred fold. Its cultivation is so general in the western parts of Africa, and even in the interior, that doubts have been therefore entertained of its American origin, of which, however, the most eminent botanists seem to be quite satisfied. The seeds are sometimes eaten raw, but more
generally boiled or roasted. In New Spain, and in some parts of Africa, they form one of the principal articles of food; but the importance of the plant is chiefly owing to the fixed oil contained in them, which is used for the same purposes as olive or almond oil, and is quite equal to olive oil either for lamps or for the table. This oil is also much used in Spain in the manufacture of soap and of chocolate. A bushel of the seeds yields one gallon of oil, when expressed cold; if heat is applied, the quantity is greater, but the quality inferior. It has become a considerable article of commerce. The A. hypogaa delights in a light and sandy, but at the same time fertile, soil. The seeds are dug up as roots or tubers usually are. The root has qualities resembling those of licorice, for which it is sometimes used. The herbage is good food for cattle. Several new species of this genus have been discovered in Brazil.