Structure of Veratrum Viride.
This liliaceous plant is a perennial herb native to eastern North America, and ranging in its habitat from Canada to the Carolinas. It prefers damp localities, such as the borders of moist thickets, the banks of mountain streams, etc. Its erect, leafy stem rises to the height of from two to seven feet and, except in the inflorescence, is unbranching. The leaves are three-ranked, simple, broadly-oval, acute or acuminate, entire-margined, basi-nerved and plicate along the principal nerves, so that on their lower surface they present a strongly-ribbed appearance. They clasp the stem at their base and so ensheath it that a cross-section of its lower portion shows it to be enclosed in a succession of thin cylinders. The lower leaves, which are from six inches to a foot long, are the broadest, those above gradually decreasing in size and relative width to linear-lanceolate bracts, next the inflorescence.
The inflorescence consists of a terminal pyramidal panicle from eight to sixteen inches long, and composed of dense spike-like racemes of greenish-yellow, monoeciously polygamous flowers, each subtended by a pointed bract.
The perianth consists of six pieces, the three outer (calyx) very similar in form and color to the three inner (corolla), except that they are a little longer. All of the pieces are distinct, or very slightly united at the base, lanceolate in outline, somewhat narrowed and thickish at the base, and ciliate-serrulate on the margin.
The androecium consists of six stamens, which are distinct, hypogynous, and shorter than the pieces of the perianth.
The gynaecium consists of a single, three-carpeled pistil, which is exteriorly three-lobed, and with three sessile, recurved stigmas. Internally, the ovary shows an axile placentation and numerous ascending anatropous ovules. The fruit is a septicidal capsule containing usually in each loculus from eight to ten flattish-oblong, membranous-margined seeds.
The plant is so similar to the European Veratrum album as to lead many botanists to regard it as only a variety of that species. The general aspect of the two plants, however, is quite different, ours having greener flowers, its panicles more compound, and the component racemes more loosely flowered and less regular, and also having its leaves more pointed. The plate illustration conveys an idea of the general appearance of the plant.
In our latitude the blossoming takes place in the latter part of June or early in July.
The rhizome is fleshy, upright or oblique, obconical, one and one-half to three inches long, and one to one and one-fourth inches thick at its upper end, and densely covered with somewhat fleshy, simple roots, about one-twelfth of an inch thick and from six to ten inches long. Those toward the somewhat truncate lower end of the rhizome are dead, or, in older rhizomes, even withered away, leaving rounded scars. In the fresh state the roots are white, the older ones closely and irregularly wrinkled, while the younger ones are nearly smooth; but in the dried form the color is yellowish or yellowish-brown, and all the roots are much shrivelled and wrinkled. The wrinkling is due to the loosely arranged and thin-walled parenchyma of the cortex, and particularly to the numerous large, lysigenous, intercellular spaces in the cortex. Toward the lower ends of the roots are numerous fine fibrils, which, however, are only sparingly present in the dried drug.
The central radial bundle of the roots is from eight to fourteen rayed, with conspicuously large scalariform ducts at the inner ends of the xylem rays, and very small ones at the exterior ends. The cells of the endodermis have their outer walls thin, but those of its cells which come opposite the phloem masses are conspicuously thickened in their inner and radial walls. Those opposite the ends of the xylem rays are usually but slightly thickened.
The rhizomes in the dried forms are dark brown, or blackish, exteriorly, usually crowned at their upper end with the remains of the solid above-ground stem, ensheathed by the numerous thin, tunicated leaf-bases. To facilitate drying, they are commonly split in a longitudinal direction, into two or more wedge-shaped or flat pieces. The fracture is short, and the color, internally, whitish. The cross-section shows a distinct cylinder sheath forming an irregular dark line between the central cylinder and the thickish cortex. The bundles are of the concentric type, with a small central phloem surrounded by two or three layers of small sized scalariform ducts and tracheids, and these are bounded exteriorly by an endodermis. The ducts and tracheids are irregular in form and direction in the bundle. The bundles also pursue a very irregular course in the rhizome, so that a cross-section cuts some of them transversely, others longitudinally, and still others obliquely, giving rise to the appearance of numerous irregular brownish dots and wavy lines, imbedded in the whitish parenchyma. In the cortex, the wavy lines and dots are also present, but less numerous, and toward the outside are seen the sections of the root-bundles near their origin.
The parenchyma of both roots and rhizome is rich in small-grained starch, and there are also in both scattered cells containing bundles of needle-like raphides.
The starch grains are sometimes nearly spherical, simple, and with a central, and often fissured, hilum; but they are more frequently compound, consisting of two, three, or sometimes of a larger number of easily separable grains. Stratification lines are only recognized with difficulty, even in the largest grains.
The writer has observed in one instance the fraudulent substitution of the rhizome and rootlets of Symplocarpus foetidus for those of Veratrum viride. The drug was so prepared that the incautious purchaser might easily have mistaken it for the genuine article, but the fraud could not have deceived a careful observer, for the roots of Symplocarpus are much coarser, averaging at least an eighth of an inch in diameter; the rhizomes also average considerably larger, the cortex is relatively thicker, the structure of the rhizome is more porous, the starch grains are much smaller, and the leaf-bases at the top are much less numerous and not tunicated. The foetid odor of Symplocarpus is also characteristic; but when the drug has been kept for some time, this odor becomes faint, or entirely disappears, and so is less reliable than the structural characters as a means of identification.
As between the rhizomes of Veratrum album and those of Veratrum viride, it would indeed be very difficult to distinguish by structural, or any other characters, if the drugs were trimmed alike. Fortunately, however, this is not the case, the rhizomes of Veratrum album having the roots mostly trimmed away, while those of Veratrum viride are not removed.