At the very outset I wish to state that coca is in no wise related to cocoa, a mistake which is very often made. The term coca, or cuca, as it is sometimes spelled, applies usually to the leaves of _Erythroxylon coca_, which are used as a stimulant by the natives of South America and which yield cocaine, a very important local anæsthetic. Cocoa or cacao refers to the seeds of _Theobroma cacao_, from which cocoa and chocolate are prepared, so highly prized in all civilized countries. With these preliminary statements I shall begin the description of coca, hoping at some future time to describe the even more interesting and important cocoa-yielding plant. Coca and cuca are South American words of Spanish origin and apply to the plant itself as well as to the leaves. The plant is a native of Brazil, Peru, and Bolivia. It is a shrub varying in height from three to ten feet. The leaves resemble the leaves of tea in general outline. The margin, however, is smooth and entire, the leaf-stock (_petiole_) short; upper and lower surfaces smooth; they are rather thin, leathery, and somewhat bluish-green in color. The characteristic feature of the leaf is two lines or ridges which extend from the base of the blade, curving out on either side of the mid-rib and again uniting at the apex of the leaf. The flowers are short pedicled, small, perfect, white or greenish-yellow, and occur singly or in clusters in the axil of the leaves or bracts. The shrub is rather straggling and not at all showy. Coca has been under cultivation in South America for many centuries. According to A. de Caudolle the plant was very extensively cultivated under the rule of the Incas. In fact it is generally believed that the original wild stock no longer exists; such eminent authorities as D'Orbigny and Poeppig maintaining that the wild growing specimens now found in South America are plants which have escaped from cultivation. Coca is now extensively cultivated in Peru, Bolivia, Brazil, and other South American countries, particularly in the Andes region. It is also extensively cultivated in British India and in Java. Attempts have been made to introduce it into Southern Europe but without success. The plants are grown from seeds sown in pots or boxes in which they are kept until they are from eight to ten inches high, after which they are transplanted during the rainy season. Coca thrives best in a warm, well-drained soil, with considerable atmospheric moisture. In the Andes region an elevation of 2,000 feet to 5,000 feet is most suitable. The young growing plants must be protected against the heat of the sun. The maximum growth is attained in about five years.