The calisaya is one of the most im portant of the "barks," inasmuch as qui nine constitutes from one-fourth to three-fourths of the total alkaloidal yield. The old "natural fiat bark," the product of felling and stripping, is no longer met with, but, instead, so far as the United States is concerned, the major portion is a yellow bark rolled from flat pieces, coming from Bolivia; there are also "quilled" and doubly-quilled varieties, of variable thicknesses, from 3 inches to 2 feet long, 1/, to 2 1/., inches in diameter and 1/„ to V, inch thick, with a longi tudinally-wrinkled and transversely-fis sured, brown epidermis, the latter prac tically tasteless and inert, and easily sep arated from the inner or medicinal por tion. This bark is of short, fibrous text ure, compact, presenting shining points wherever broken, of brownish-yellow hue, faint odor, and bitter, slightly-as tringent taste.
'The red bark, has many alkaloids, but does not yield as much quinine as the calisaya. It comes in quills and flat pieces, varying in thickness from 1/8 to 1/4 inch, is of deep-brown or brown-red color, and gives a short, fibrous fracture. The epidermis is covered with warts and ridges; the inner surface rather coarsely striated. It gives a powder of a deep brown-red hue that is slightly odorous, but astringent and bitter.
Pale barks also come in cylindrical pieces of variable length, sometimes singly, sometimes doubly "quilled," are from 1/6 to 1 inch in diameter and from 1/24 to 1/, (more rarely 1/4) in thickness. The exterior surface is rough, of a gray ish color, with transverse, and sometimes longitudinal, fissures; interior surface either rough or smooth, according to the period of gathering; fracture smooth, with some short filaments on the inner surface; faintly-aromatic odor, and mod erately bitter and astringent taste. Of the total alkaloids, from 50 to 65 per cent. is quinine.
Huanuco, or gray bark, of a cultivated variety and much richer than the pale forms in qninine, is now obtained from Jamaica. The quills are frequently somewhat spirally rolled, and on the epi dermis are numerous short, irregular, transverse cracks; the edges are flat, scarcely separated or everted; the outer surface is whitish or of a clear silvery gray, or in the smaller quills of a uniform whitish-gray; inner surface yellow, yel lowish-red, sometimes cinnamon-brown; smooth in small quills and fibrous in large; fracture smooth and resinous, odor clayish and pleasant; taste astringent, aromatic and bitter. The bark from C.
nitida is not wrinkled longitudinally on the derm, and the inner portion is of a more or less brown hue; but the product of C. micrantha is often wrinkled longi tudinally, though almost devoid of trans verse fissures; it has a rusty-yellow in terior. As obtained uncultivated from South America, these gray barks yield less than 3 per cent. of alkaloids, often but 1.5 per cent., of which but from 3/io to 3/5 per cent. is quinine.
Columbian, or Cartagean, barks are of two forms. That from C. lancifolia is chiefly from young stems and branches, are usually "quilled" and coated with a brownish-yellow epidermis, in turn perhaps coated with white crustaceous lichens, causing it to assume a -grayish or silvery appearance. The quills -vary in size from 5/8 to 11/2 inches in diameter, some being rather smooth, others rough, owing to numerous short, slight, longi tudinal and transverse cracks; edges slightly everted; extremely fibrous and moderately bitter. It is not uncommon to find the "quills" trimmed: i.e., with the epidermis removed. The interior may be reddish, orange-yellow, or yellow; hence it is not always easily distinguished from the gray barks. The cordifolia form occurs both as flat pieces and as fine, middling, and thick quills; the flat pieces more or less twisted, arched, and v,-arped; from 1/2 to 2 inches broad, 4 to S or 12 inches long, and 1/, to 3/, inch thick. The quills vary from 5 to 12 inches in length, are from 1/, to 3/, inch in diameter, and 1/„ to V, inch thick, and also are frequently deprived of epi dermis. The interior surface of both forms varies from smooth to fibrous, the prevailing hue being of a pale-oehre yel low, in old species brownish. The fibres often project obliquely, giving a scaly, fibrous appearance. The epidermis, when present, is observed of a whitish, yellow ish-white or ash-gray hue, with irregular, flexuous, longitudinal, but not very deep furrows. The fracture, if transverse, is short, internally more or less fibrous, ex ternally corky; longitudinally it is un even, short, coarse, and splintery, and often effected only with difficulty. The powder is of cinnamon-hue, moderately bitter and astringent. Both the fore going barks vary materially in their yield of alkaloids.
Petaya bark is of little interest save to manufacturers of alkaloids, and con tains from 1.5 to 1.8 per cent. of quinine. It comes in short quills or curly pieces of a brownish color, and is especially rich in quinidine.