CONVALLARIA
.
By OTTO A. WALL, M.D., Ph.G.
Cnovallaria Majalis is a stemless perennial plant, found in both the eastern and western hemispheres, with two elliptic leaves and a one-sided raceme bearing eight or ten bell-shaped flowers. The flowers are fragrant, and perfumes called "Lily of the Valley" are among the popular odors.
Both leaves and flowers have been used in medicine, but the rhizome is the part most frequently used.
CONVALLARIA.
The fresh rhizome is a creeping, branching rhizome of a pale yellowish white color, which, on drying, darkens to a straw color, or even a brown in places. When dry it is about the thickness of a thick knitting needle, swelling to the thickness of a quill when soaked in water. It is of uniform thickness, except near the leaf-bearing ends, which are thicker marked with numerous leafscars, or bare buds covered with scales, and often having attached the tattered remains of former leaves. Fig. A shows a portion of rhizome, natural size, and Fig. B shows another piece enlarged to double linear size.
The internodes are smooth, the rootlets being attached at the nodes. The rootlets are filiform, and darker in color.
The rhizome is covered by an epidermis, composed of muriform cells of a bright yellow color, after having been treated with liquor potassæ to clear up the tissues. These cells are shown in Fig. G. An examination of the transverse section shows us the endogenous structure, as we find it also in various other drugs (sarsaparilla, etc.), namely, a nucleus sheath, inclosing the fibrovascular bundles and pith, and surrounded by a peri-ligneous or peri-nuclear portion, consisting of soft-walled parenchyma cells, loosely arranged with many small, irregularly triangular, intercellular spaces in the tranverse section. Some of these cells contain bundles of raphides (Fig. 2), one of which bundles is shown crushed in Fig. J. Sometimes these crystals are coarser and less needle-like, as in Fig. K. Fig. C shows a transverse section through the leaf-bearing portion of the rhizome (at a), and is rather irregular on account of the fibrovascular bundles diverging into the base of the leaves of flower-stalks. A more regular appearance is seen in Fig. D, which is a section through the internode (b). In it we see the nuclear sheath, varying in width from one to three cells, and inclosing a number of crescent-shaped fibrovascular bundles, with their convexities toward the center and their horns toward the nuclear sheath. There are also from two to four or five free closed fibrovascular bundles in the central pith.