“Leaves alternate, 1½ to 2 inches long, membranous, flat, opaque, acute at both ends, the apex almost mucronate; quite entire, dark green above, pale beneath, 3-nerved in the middle, with fine connecting veins. Petiole 2-4 lines long, with a pair of intra-petiolary ovate-lanceolate brown acute stipules, upon the back of the outside of which, indeed, the petiole is articulated, and from which the leaf readily falls away, leaving the branches scaly with the persistent stipules. Flowers numerous, in fascicles from the branches where the leaves have fallen away, bracteated. Peduncles about as long as the flower, sharply angled. Calyx 5-cleft; segments acute. Petals alternate with the calycine segments, oblong, concave, wavy, with a lacerated and much plaited membrane arising from within and above the base. Stamens 10; filaments longer than the pistil, combined below into a rather short cylindrical tube. Ovary oval. Styles 3, about as long as the ovary. Stigmas thickened. Fruit a 1-seeded, oblong drupe, in a dry state obscurely furrowed. Nut of the same shape and furrowed. A powerful stimulant of the nervous system, affecting it in a manner analogous to opium. Less violent in its effects than that drug, but more permanent in its action.”
The chromo-lithograph [Frontispiece] is from a water-colour, by Mr. J. Allen, of the plant in flower at Kew.
1. Sprig of Erythroxylon Coca.
2. Back of Leaf (full size).
3. Flower (enlarged).
4. Fruit.
The leaves vary much in shape on the same plant even, the upper and lower are different, and, probably owing to much cultivation and numerous varieties, the dried leaves in commerce are very variable in size and appearance, shape and colour, as well as state of preservation. They are usually one to two inches long, but large varieties are often four or five inches long. They are oval oblong, but some are ovate, while others are obovate, entire on the margin, sometimes acuminate, but usually blunt and emarginate, and often with an apiculus in the notch at the apex; rather thin, smooth, with a prominent midrib, and on each side a curved line running from the base to the apex. The fresh leaves are paler in colour beneath, and a bloom on the surface gives them a dichroic appearance; in one direction the upper surface appears yellowish green, whilst if looked at direct it is dark green. The dried leaves have a slight odour of tea, and a somewhat grass-like, bitter, aromatic taste; in colour they vary from a pale bright green, changing to a yellowish green (North Peruvian or Truxillo and Huanuco varieties)—this is smaller, thinner, and much broken—to a dull brownish olive (Bolivian variety), this is larger, broader, and a thicker leaf, not broken, paler in colour beneath; the inner curved lines from base to apex are very marked on this, but only faintly on the Truxillo variety, in some leaves hardly discernible. These two varieties shade off into each other. The Truxillo variety is imported principally from Salaverry, and, according to Hesse, is the product of Erythroxylon Coca, var. Novo-granatense, Dyer. The variety from Southern Peru is, he says, exported viâ Lima, that from Bolivia from Arica and Mollendo. Huanuco and Cusca cocas are known in the markets as coming from provinces adjacent to these towns, where commercial houses have their headquarters. Some of the Coca finds its way to Europe through Para, the port at the mouth of the Amazon.
Hesse says he obtains from these South American Cocas, 0·7 to 0·9 per cent. of alkaloids, of which the greater part consists of crystallizable cocaine in the broad-leaved variety, and about one-half in the narrow-leaved or Truxiilo Coca.—P.J. 1891, 1109.
In selecting them, care should be taken that they have not fermented or become fusty—they may appear of a good green colour, yet have a mouldy taste. The leaves are also collected from wild plants which have strayed from cultivation. The original habitat of the Coca plant is not known; it has been acclimatised in Java, Ceylon, and some parts of India.
Burck attributes the plant cultivated in British India to a new species—Erythroxylon Bolivianum, Burck—and that cultivated in Java to a distinct variety, E. Coca, var. Spruceanum. The Cocas from these sources, as well as from Ceylon, have not proved satisfactory in their yield of cocaine. According to Hesse, the alkaloids accompanying it considerably preponderate, the base frequently consisting principally of cinnamyl-ecgonine methyl ester.—P.J. 1891, 760, 1109.