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Class XIV. DIDYNAMIA. Order II. ANGIOSPERMIA.
tricose. Capsule ovate, two-celled. Spe. Char. Segments of the calyx ovate, acute. Corolla obtuse,
upper lip undivided. Leaves downy.
The root is biennial, and fibrous; the stalk is erect, simple, tapering, covered with fine hairs or down, and grows to the height of four or five feet; the leaves are large, oval, narrowed towards their points, obtusely serrated, veined, downy, and stand upon short-winged footstalks; the floral leaves or bracteæ, are spear-shaped, sessile, and purplish towards the point; the calyx consists of fine segments, which are eliptical, pointed, nerved, or ribbed, and the uppermost segment is narrower than the others; the flowers grow in a long terminal spike, chiefly on one side; they are large, monopetalous, pendulous, bellshaped, purple, and marked on the inside with little eyes, or dark coloured dots, placed in whitish rings; the tubular part appears inflated, and almost cylindrical, but swelling towards the base, and opening at the limb into four irregular, short, obtuse segments; of these the uppermost is the shortest, appearing truncated or cut off transversely; the peduncles are round, short, villous, and bend downwards by the weight of the flowers; the filaments are two long and two short, white, crooked, inserted in the bottom of the tube, and crowned with large oval yellow anthers; the style is simple, and thickening to
wards the stigme, which is bifid; the germ is oval, and surrounded at the bottom by a small nectarious gland; the capsule is bilocular, and contains many blackish seeds. It grows usually by the road-sides and ditches and hedges, especially in dry gravelly soils, and flowers in June and July.
The leaves of the Foxglove have a bitter, nauseous taste; it grows wild in most of the temperate countries of Europe and in the United States, and is often cultivated in gardens for ornament and medicinal purposes. The leaves are the part usually employed, although the seeds are recognized as being officinal. Much care is requisite in selecting, preparing, and preserving Foxglove, in order to insure its activity.
Medical Properties and Uses. Digitalis is narcotic, sedative, and diuretic-a violent poison, but yet a valuable medicine and when administered in quantities is apt to produce a sense of tightness, or weight, with dull pain in the head, vertigo, dimness, or other disorder of the vision and of the mental operations; externally it has been used in sores and scrofulous tumours with considerable advantage. Respecting the internal use of this plant, we are told of its good effects in epilepsy, scrofula, and phthisis, but the incautious manner in which it has been employed renders it a very dangerous remedy; yet while Digitalis was generally known to possess such medicinal activity, its diuretic effects, for which it is now deservedly received in the Materia Medica, were wholly overlooked. To this discovery Dr. Withering has an undoubted claim; and the numerous cases of dropsy related by him, and other practitioners of established reputation, afford incontestible evidence of its diuretic powers, and of its practical importance in those diseases.
The dose of the dried leaves, in powder, is from one grain to three, twice a day; or three grains of the leaves, tinctured in spirit, may be taken instead of the powder.