Colchicum autumnale. Colchicum.
Nat. Ord. — Melanthaceae. Sex. Syst. — Hexandria Trigynia.
Cormus or Bulb, and Seeds.
Description. — This plant, also called Meadow Saffron, is a perennial bulbous plant. The corm is large, ovate, solid, fleshy. The leaves are dark-green, very smooth, obtuse, above a foot long, an inch and a half broad, carinated, produced in the spring, along with the capsules. Flowers several, radical, leafless, bright purple, with a long white tube appearing in the autumn without the leaves. Capsules three, distinct, though forming together a single, oblong, elliptical fruit, with intermediate fissures. Seeds whitish, polished.
History. — Colchicum grows in meadows, and low, rich situations in many parts of Europe, and is common to England. The herb is annual, but the root is annual or perennial according to the manner in which the plant is propagated, which may be from the seed, by the formation of a single mature bulb from a parent bulb, or by the separation of several immature bulbs from the parent. The manner of growth of the plant deserves a brief notice. In the latter part of the summer, a new bulb or cormus commences forming at the lateral inferior portion of the old one, which receives the young offshoot in its bosom, and embraces it half round. The new plant sends out fibers from its base, and is furnished with a radical, cylindrical, tubular spathe, cloven at top on one side, and half under-ground. In September from two to six lilac or purple flowers emerge from the spathe, and unaccompanied with leaves ; by the end of October these flowers perish, and the rudiments of the fruit remain under-ground until the next spring, when the leaves rise upon a stem above the surface, elevating along with them the germ en consisting of three many-seeded capsules, which ripen their seed about midsummer; after this the plant speedily dies and withers. While the flower is rising in the autumn, the bulb is very small, but in the winter it grows rapidly, being in April as large as a chestnut, and attaining its greatest size, about that of a small apricot, in July. It is now a year old, and the herb having matured its seed, is withering away, but a new bulb begins to appear at its lower end, close to its junction with the radicles or root proper, which passes through a similar succession of changes ; while the old parent bulb, gradually becomes more spongy and watery, but retains its size until the following April, the second spring of its own existence, when it quickly decays. The seeds and the bulb are the officinal parts of the plant. The bulb attains its greatest perfection about the' beginning of July, at which time it should be gathered for medical use. It resembles a small tulip root, rounded on one side, flattened on the other, being brown externally, white internally, and containing an acrid, milky juice. The odor is kircine, and the taste unpleasant, bitter and acrid. In drying, the bulb is usually cut into thin transverse slices, having first been stripped of its external dark brownish-black membranous tegument, and is dried quickly ; sometimes it is dried entire.
Good colchicum bulbs when dried are of an oval-rounded form, with a notch or deep groove on one side, of a grayish-white color, an amylaceous appearance, firm, dry, and capable of changing their color to blue when softened with distilled vinegar, and then touched with tincture of guaiacum. Its odor is much less than in the fresh bulb, and its taste bitter, hot and acrid. Alcohol, wine, or vinegar extracts its virtues. The acetic tincture is generally preferred to the vinous, as it is not so liable to change or decomposition. Acids render the vinous tincture drastic, while alkalies render its operation milder. It contains a vegetable alkali combined with an excess of gallic acid ; a fatty matter composed of olein, stearin, and a peculiar volatile acid analogous to the cevadic; a yellow coloring matter; gum ; starch ; inulin in large quantity, and lignin. The alkaline principle, formerly supposed to be identical with veratria, has been found to be peculiar, and has received the name of Colchicia. Solution of iodine causes a blue precipitate with the decoction of the bulb ; the acetate of lead, nitrate of protoxide of mercury, and nitrate of silver cause white precipitates ; and the tincture of galls a slight precipitate.
Colchicum seeds should be gathered about the beginning of August, when they are fully ripe; they are rough, roundish, dark-brown externally, white within, about the eighth of an inch in diameter, and of a bitter, acrid taste. It was formerly supposed that their active properties resided in the husk or testa, and it was advised not to bruise them in making the tincture, but recent experiments have proved that the bruised seeds yield the strongest tincture. Their properties are similar with those of the bulb, and as they are considered more uniform in strength than the bulb, they are usually preferred to it.
Colchicia may be obtained by a process similar to that employed in the preparation of hyoscyamia from hyoscyamus. (See the article Hyoscyamus). A simpler process is to digest the seeds of colchicum in boiling alcohol, precipitate the tincture with magnesia, treat the precipitated matter with boiling alcohol, and finally filter and evaporate. It is crystallizable, bitter, and very poisonous, and does not, like veratria, cause sneezing when applied to the nostrils, is more soluble in water, and has less poisonous influence on the system. It is soluble in water, alcohol, and ether; nitric acid colors it blue or violet ; its salts are crystallizable, acrid, bitter, and poisonous. In a very small dose it causes purging and vomiting.
Properties and Uses. — In large doses, an acro-narcotic poison. Medicinally, sedative, cathartic, diuretic, and emetic. Used in gout and gouty rheumatism, dropsy, palpitation of the heart, gonorrhea, enlarged prostate, etc. Care must be used in its employment. It sometimes increases the uric acid in the urine of arthritic patients; and has been beneficially employed in febrile, inflammatory and nervous affections, and in chronic bronchial complaints. A good acetic tincture may be made by macerating an ounce and a half of the dried bulb, or seeds, in twelve fluidounces of the strongest vinegar for fourteen days. Then filter, and keep in well-stopped bottles. The dose for an adult is from thirty to sixty drops, as often as may be required. An acetic extract may be prepared, containing all the powers of the plant, by rubbing the bulbs to a pulp to the quantity of a pound, and gradually adding acetic or pyroligneous acid three fluidounces. Express the liquid, and evaporate it in an earthen vessel not glazed with lead, to the proper consistence ; the dose is from one to three grains, three or four times a day. Dose of the dried bulb, from one to eight grains, gradually increased every four or six hours, till the effects of the medicine are obtained.
Off. Prep. — Tinctura Colchici Composita; Tinctura Colchici Seminis ; Vinum Colchici Radicis; Vinum Colchici Seminis.