(The Cypripediums are rare and endangered orchids. Don't use them unless you grow them yourself. -Henriette.)

Cypripedium. N. F. IV (U. S. VIII). Lady Slipper. Rhizoma Cypripedii. Yellow Lady Slipper Root. Yellow Indian Shoe. Yellow Moccasin Flower. Yellow Noah's Ark. Venus' Shoe. Male Nervine. American Valerian. Racine de Cypripede jaune, Valeriane americaine, Fr. Gelbfrauenschuhwurzel, G.—"The dried rhizome and roots of Cypripedium hirsutum Miller, Cypripedium pubescens Willdenow, or of Cypripedium parviflorum Salisbury (Fam. Orchidaceae), without the presence of more than 5 per cent. of other parts of the same plants or other foreign matter." N. F. IV.

Under the common name of lady's slipper, or moccasin plant, several species of Cypripedium inhabit the woods in different parts of the United States. They are small plants, with large, many-nerved, plaited leaves, sheathing at the base, and large, often beautiful flowers, of a shape not unlike the Indian moccasin, whence they derive one of their common names. Several of them have been used by American physicians, the root being the part employed. R. P. Stevens of Ceres, Pennsylvania, says of them that he has found the C. reginae Walt. (C. spectabile Salisb.), and C. acaule Ait., especially when growing in dark swamps, to be possessed of narcotic properties, and to be less safe than the C. parviflorum Salisb., which is gently stimulant with a tendency to the nervous system, and is quite equal to valerian. He has employed it advantageously in hysteria, and in the pains of the joints, following scarlet fever. (N. Y. Journ. Mod., iv, 359.) E. Ives considers C. hirsutum Mill. and C. reginae Walt. identical in their effects, but C. reginae more powerful. (Trans. Am. Med. Assoc., iii, 312.) The roots of the two species, C. hirsutum and C. parviflorum are indiscriminately found in commerce and sold under the same name.

Cypripedium parviflorum var. pubescens or large yellow lady's slipper, has a simple, often flexuous, pubescent, leafy steam, from one to two feet high. The leaves are pubescent, ovate-lanceolate, acuminate, narrowing at the base, about four or five inches long by two in breadth, alternate, sessile, and sheathing. The flower is usually solitary and terminal, with four divisions of the perianth, the two outer cohering nearly to the apex, the inner longer, narrower, undulatory or twisted, and the lip an inch or two in length, swelling sac-like, and of a yellow color. The fruit is an oblong capsule, tapering at each end, recurved, pubescent, and peduncled. The plant is indigenous, growing abundantly in rich, moist woods throughout the United States.

Cypripedium parviflorum. Small-flowered Yellow Lady's Slipper, is a perennial plant with a leafy stem, a foot or two in height, and comparatively small yellowish-green flowers, appearing in May. The specific character of the flower, which is that also of the plant, is that the lobe of the style is triangular and acute; the outer petals are oblong-ovate and acuminate; the inner linear and contorted; the lips shorter than the petals, and compressed. This species grows extensively through the United States, south of the Potomac, east and west of the Alleghanies, and in several of the Northern States, particularly New York, Michigan, Connecticut and Vermont.

It is described by the N. F. IV as a "rhizome of horizontal growth, curved, from 3 to 10 cm. in length, and from 2 to 6 mm. in thickness, orange-brown to dark-brown, the upper side showing numerous circular, cup-shaped scars, closely covered below with simple, wiry roots, varying from 3 to 15 cm. in length; fracture of rhizome short, white, that of roots somewhat fibrous. Odor distinct, heavy; taste sweetish, bitter, and somewhat pungent. The powdered drug is yellowish-brown and, when examined under the microscope, exhibits numerous rounded or somewhat angular, simple and compound starch grains up to 0.014 mm. in diameter; calcium oxalate in raphides up to 0.065 mm. in length and occurring isolated or in bundles, occasionally imbedded in a. mucilage-like plasma; tracheae spiral, scalariform, or with simple or bordered pores; a few tracheids; sclerenchyma fibers, long, thin-walled and lignified; a few non-lignified, thick-walled fibers; fragments of epidermal tissue composed of elongated cells with reddish-brown walls; groups of thick-walled parenchyma cells with numerous simple pores. Cypripedium yields not more than 12 per cent. of ash." N. F. Maisch gave a distinctive description of the roots of the two species. (A. J. P., 1872, 297.) Poisonous properties have been attributed to C. reginae Salisb. and C. parviflorum var. pubescens (see Geol. Nat. Hist. Survey, Minnesota, Bull., 9, part i), but it has been shown that the secretion from the glandular hairs simply exerts an irritant action.

Senega and hydrastis roots are sometimes found accidentally mixed with those of cypripedium, probably from the plants having a common habitat.

Cypripedium has a somewhat aromatic odor, which diminishes by time, and a bitter, sweetish, peculiar, and in the end somewhat pungent taste. Henry C. Blair found it to contain a volatile oil, a volatile acid, tannic and gallic acids, two resins, gum, glucose, starch, and lignin. (A. J. P., 1866, p. 494.) The eclectic preparation cypripedin is said to be a resinoid, obtained by precipitating with water a concentrated tincture of the rhizome. The substance thus obtained is complex, and has no claim to the name given it, which ought to be reserved for the active principle when discovered. It is probable that the virtues of the rhizome reside in a volatile oil and a bitter principle.

Cypripedium appears to be a gentle nervous stimulant or antispasmodic, and has been used for the same purposes as valerian, though less powerful. E. Ives of New Haven, Conn., commends the remedy in hypochondriasis and neuralgia. It may be used in powder, infusion, or tincture.

Dose, of the powder, fifteen grains (1.0 Gm.), three times a day. The resinoid, obtained by precipitating the tincture, has been given in doses varying from half a grain to three grains (0.032 to 0.20 Gm.).

The Dispensatory of the United States of America, 1918, was edited by Joseph P. Remington, Horatio C. Wood and others.