Daphne mezereum. Mezereon.
Nat. Ord. — Thymelaceae. Sex. Syst. — Octandria Monogynia.
Description. — Mezereon, or Spurge Olive, is a very hardy shrub, with a large root, and bushy stem four or five feet high, with upright, alternate, smooth, tough, and pliant branches, leafy when young, and a smooth dark-gray bark, which is easily separable from the wood. The leaves spring from the end of the branches, they are deciduous, scattered, sessile, obovate-lanceolate, entire, smooth, of a pale-green color, somewhat glaucous beneath, and about two inches long ; they appear after the flowers, and accompanied with the flower-buds of the next season. The flowers are in clusters, each consisting of two or three flowers, forming a kind of spike at the upper part of the stem and branches, sessile on the naked branches, with several brown, smooth, ovate bracts underneath ; they are of a pale-rose color, very fragrant, and consist of a hypocrateriform calyx, crimson all over, and the tube externally hairy. Segments of the calyx four, deep, ovate, spreading. Stamens eight, alternately longer, inserted into the tube, and having roundish, oblong anthers. Ovary ovate, superior, bearing a short style with a flattish, entire stigma. The fruit is a pulpy, scarlet, oval, shining berry, containing a single seed.
Daphne Gnidium is a small bush, with the leaves linear-lanceolate, clustered, acuminate, cuspidate, quite smooth. The flowers are numerous, small, white, downy, fragrant, and in terminal panicled racemes. The fruit is globular, dry, at first green, but ultimately black.
Daphne Laureola or Spurge-laurel is a smooth plant, with a stem two or three feet high, and round, pale, brown, upright, tough and pliant branches, crowned with tufts of evergreen leaves, elegantly drooping in all directions, and about two or three inches long, lanceolate, glabrous, acute, entire, subsessile. Flowers deep-green, with orange anthers, four of which are just visible in the throat of the calyx, five together in each axillary raceme. An oval, concave bract accompanies each short partial stalk, at the base. Berry oval, black.
History. — All the species of Daphne possess active properties, but the bark met with in commerce is usually obtained from the three above described, that from the latter being less active than the others. The D. Mezereum is a native of the northern parts of Europe, where it is cultivated both as a medicine and an ornament ; it flowers very early in the spring, often before the snow has disappeared. The D. Gnidium is found in the south of France on hills and barren plains, and its bark is employed there indiscriminately with that of the other species.
The bark of the root is the officinal part, but much that is obtained in the shops is derived from the stem. The D. Mezereum is the most active plant of the genus ; its bark is generally collected in the spring. It is met with in flat or quilled pieces, from two to four feet long, and an inch or less in breadth, always folded in bundles, or in the shape of balls. Externally, it is covered with a grayish, or reddish-brown wrinkled epidermis, very thin, and easily removed from the bark, and beneath which is a soft, greenish tissue. The inner bark is tough, pliable, fibrous, striated, of a yellowish-white color internally, and an olive or brownish hue externally. Its smell when fresh is faint and disagreeable, but on drying it becomes inodorous ; its taste is at first sweetish, soon followed by intense and durable hot acridity. It yields its virtues to water by decoction, likewise to alcohol ; and it unites with oils or fats, forming an excellent ointment. It contains an acrid resin, a yellow coloring matter, a reddish-brown extractive matter, an uncrystallizable and fermentable sugar, a gummy matter containing azote, ligneous fiber, malic acid, several malates, and a peculiar principle named Daphnin.
Daphnin may be obtained by treating the alcoholic extract of the bark with water, decanting the solution, precipitating with subacetate of lead, filtering, decomposing the excess of the subacetate by sulphureted hydrogen, — again filtering, evaporating to dryness, submitting the residue to the action of anhydrous alcohol, and evaporating the alcoholic solution to the point of crystallization. It is in colorless, transparent, brilliant, prismatic crystals, slightly soluble in cold water, very soluble in boiling water, ether, and alcohol, inodorous, and of a bitter, somewhat austere taste. It is not, however, the principle upon which the virtues of the bark chiefly depend ; this is supposed to be a volatile oil, which slowly passes to the state of an acrid resin. It may be obtained by boiling mezereon in alcohol, allowing the liquor to cool in order that it may deposit some wax which it has taken up, then distilling off the alcohol, and treating the residue with water, which leaves the resin ; it is dark-green, hard, brittle, and of an exceedingly acrid and persistent taste. When boiled with water some of the acrid principle of mezereon bark passes off, which is not the case when boiled with alcohol.
Properties and Uses. — In large doses, mezereon is an irritant poison, causing redness and vesication of the skin when left in contact with it, and causing, when swallowed, dryness and burning of the throat, vomiting, hypercatharsis, and frequently renal irritation. The berries have proved fatal to children who have eaten them ; yet in some countries they are used as a purgative, in doses of eight to twelve. In small doses it acts as a stimulant, alterative, diuretic, diaphoretic in warm decoction, and cathartic. It acts favorably in syphilis, mercurio-syphilis, scrofula, chronic rheumatism, and some forms of obstinate disease of the skin. Dose of the decoction, from one to three fluidounces ; of the powder ten grains.
Externally, it is seldom used by Eclectics ; sometimes employed by other practitioners to produce rubefaction and vesication, and in the form of ointment as an application to blistered surfaces, indolent ulcers, and issues, in order to keep up a discharge. When vesication is desired, the bark is moistened with vinegar, after having been cut in the requisite form and size, and applied to the skin ; it is renewed twice a day, until a blister is formed. It is slow in its operation, frequently requiring forty-eight hours to vesicate.
Off. Prep. — Decoctum Sarsaparillae Compositum ; Unguentum Mezerei.