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Class XIX. SYNGENESIA.-Order II. POLYGAMIA.
NATURAL ORDER, COMPOSITÆ RADIATÆ.
Fig. (a) represents a foret of the ray with the bifid pistil; (6) a foret of the disc, both slightly magnified; (c) the fruit, which is an achenopsis, with its pappus or down; (d) a floret of the disc, much magnified and spread;' showing the situation of the pistil, with the five united anthers, and the insertion of the filaments into the tube of the corolla. The stem on the right exhibits the situation of the fruits, with their hairy crowns, and part of the naked receptacle from whence they have been removed.
Colt's-root is one of the most common of our native plants, being found in profusion in most parts of the kingdom and throughout Europe ; growing in moist, shady situations, especially on a chalky or marly soil, in waste places, on the banks of rivers, and in gardens, where it frequently proves a very troublesome weed. The clayey parts of the pestilential maremmes of Tuscany, where scarcely any other plants will grow, are covered with common colt’s-foot. It is a perennial, flowering from the middle of March to the end of April, but the leaves do not appear in full luxuriance till the month of May. The name Tussilago is derived from tussis and ago, in allusion to its pectoral powers, and Farfara, from the resemblance its leaves bear to those of the white poplar, called by the Greeks, Farfarus.
The root is very long, frequently penetrating to the depth of several feet, and sending out many slender fibres, which creep horizontally. The scape, or flower stem, appears before the leaves; it is erect, slender, round, woolly, slightly furrowed, six or eight inches high, and clothed with numerous lanceolate scales. Several stems generally issue from the same root, each supporting a single flower about an inch in diameter, and of a bright yellow colour. The colour of the stem, as well as the scales, varies from pale green to reddish brown. The leaves are radical, cordate, on channelled footstalks, slightly lobed, and toothed; smooth above with reddish veins, but white and woolly underneath: when young the leaves are revolute, and covered with a cottony down, which easily wipes off. The scales of the involucrum are lanceolate-linear, equal to the length of the disc; erect at first, but afterwards become reflexed. The inflorescence is compound; the florets of the ray are ligulate and very numerous, always fertile, and twice the length of those of the disc, which are few in number and often barren; the central florets are tubular, with five equal segments. The achenopsides are smooth, oblong, compressed, and the seeds often abortive. The pappus is pilose, silvery, sessile, and permanent. The receptacle is naked, flat at first, but afterwards becomes convex.
The beautiful wing-like pappus with which the seeds are so plentifully provided, renders Colt's-foot peculiarly a plant of passage, and no sooner is a fit soil exposed, than it becomes covered with young plants of Colt's-foot, although none may have previously been growing within many miles. This has led sometimes to the ignorant belief, that this plant is generated spontaneously by clayey soils, the facility with which it seeds are transported either not being known, or not being duly considered. It is, however, one of many such admirable provisions of nature, that plants with long penetrating roots, such as thistle, colt's-foot, &c., should be furnished with ready means of migration, and that they should flourish chiefly in clay-bound soils, which they thus, by their burrowing roots, perforate and drain.
QUALITIES.—The root is mucilaginous and bitterish; the leaves are inodorous, and have a rough subviscid taste like that of artichokes. “The mucus they contain is yielded to water by decoction, and evolves, by boiling, a peculiar odour."
MEDICAL PROPERTIES AND Uses.—The dried leaves of this plant generally form the basis of British herb tobacco, and amongst the ancients it was famed for its pectoral and vulnerary properties. Dioscorides, Pliny, and Galen, recommend it to be smoked through a funnel or reed, and in a work, “ De Internis Affectionibus,” Ed. Fæs. p. 532. 1. 34, attributed to Hippocrates, the root, Buxoov, taken in honey, is recommended for ulcerations of the lungs. Dr. Cullen, on the authority of Fuller, employed its expressed juice in scrophulous cases, administering several ounces a day; and in some instances he thought that it favoured the healing of scrophulous sores: subsequent experience, however, has not confirmed its power over the lymphatic system. During the last century, both the leaves and the flowers were recommended for their demulcent and expectorant virtues; and old Gerard, in his “ Herball, or General historie of Plants," says, “the fume of the dried leaues taken through a funnel, burned upon coles, effectually helpeth those that are troubled with the shortnesse of breath, and fetch their wind thicke and often, and breaketh without peril the impostumes of the breast. Being taken in the manner as they take tobaco, it mightily preuaileth against the diseases aforesaid.” But although Colt's-foot still retains a place in the London Pharmacopæia, it is seldom used; and independently of its mucilaginous qualities, it may be considered an unnecessary and useless article of the materia medica.
A nostrum (says Professor Burnett), which is well known under the name of “Essence of Colt's-foot," consists of equal parts of the Balsam of Tolu, and the Compound Tincture of Benzoin, to which is added double the quantity of rectified spirits of wine. This composition, which contains no Colt's-foot, is certainly one of the most baneful medicines that could have been imposed upon the public in pectoral cases. The injurious tendency of warm resinous substances in pulmonary consumption has been pointed out, in a Dissertation by the late Dr. Fothergill. In a slight cold, the foundation of a suppuration of the lungs is laid by their use, from their increasing the inflammatory disposition, and exciting general fever; and hence it is not improbable, as a popular writer justly remarks, that more fatal cases arise in pulmonary complaints from the officious interference of domestic practice, or the nostrum of the patent warehouse, than from the really incurable nature of such maladies. Consumptive patients who take such an exhilarating, but pernicious cordial, may be compared to a flower on the bank of a river-it blossoms luxuriantly for a season, but the moisture that feeds its roots, undermines its foundation.
Those who wish to exhibit Colts-foot, on account of its demulcent properties, generally boil a handful of the leaves in two pints of water, to one pint; and the decoction, after being strained, is sweetened with honey or coarse sugar. The dose is a teacupful.
A kind of tinder, or touchwood, is, in some countries, made of the roots, impregnated with nitre. The leaves have been used as stuffing for pillows and cushions.
It may not be out of place here to notice that singular property of seeds by which they are preserved in the ground for ages. It appears from certain circumstances, that when they are buried below that particular depth at which they feel the influence of the atmosphere and consequently vegetate, they are in a state of preservation which may and does often continue for centuries—perhaps, for aught we know to the contrary, to the end of the world, if undisturbed; certainly, however, to an amazing extent of time. By this beautiful law of the all-wise Creator, the vegetable tribes are never likely to be lost. However cultivation or carelessness may tend to extirpate certain species, their seeds lie in myriads in the treasury of the earth, and some event such as we sometimes witness, the lowering of a hill, the cutting of a single turf, exposes them to the action of the air, and forth they spring. Thus it is that farmers are frequently surprised on ploughing up a field that has lain in lea beyond the memory of man, to see a plentiful crop of various and unusual plants spring up. So I have observed in Sherwood Forest, that where turf is pared, henbane is almost sure to exhibit itself, though none has been seen in the neighbourhood for years. Many instances of this kind have no doubt attracted the attention of all curious lovers of Nature.