MEDICINAL PARTS. The whole plant.
    Description. -- While traveling in Paraguay, South America, some years ago, I became acquainted with a species of Eupatorium or Lungwort called Aya-pana, possessed of most extraordinary virtues in consumption and other diseases of the chest. In Paraguay, which is a very paradise on earth, numerous medicinal herbs of exceeding great value grow to the greatest perfection. The Aya-pana belongs to the class of Eupatorium Perfoliatum, though quite unlike the Lungwort and Thorough-wort, indigenous to North America. The Aya-pana is only found on the eastern slope of the Andes, on the mountain sides, along the sunny banks of streams, and beautifully luxuriant on all the tributaries to the Amazon, and La Plata especially. It is a perennial plant, with numerous erect, round, hairy stems, five to ten feet high, the stalk plain below, but branching out in numerous stems near the top. The leaves grow on the opposite sides of the base. The direction of each pair of leaves is at right angles with that of the pair either above or beneath. The leaves are long and narrow, broadest at the base where they coalesce, gradually tapering to a serrated point, wrinkled, palish green on the under surface, and beset with white silken hairs, which add much effect to their greenish-gray color. The flowers are snow-white, slightly tinged with a purplish hue at the end, very numerous, supported on hairy peduncles. The calyx is cylindrical, and composed of imbricated, lanceolate, hairy scales, inclosing from twelve to fifteen tubular florets, having their border divided into five spreading segments. There are five black anthers united in a tube, through which a bifid filiform style projects above the flower, rendering the whole a beautiful and picturesque plant.
    History. -- It flowers constantly during the dry or sunny season, the blossoms and leaves being only used for medicinal purposes. The flowers are better than the leaves, have an aromatic odor, resembling slightly chamomile, and possess a strong bitter taste, somewhat like horehound or quassia, which virtue is imparted either to water or alcohol. Resin, gum, balsam, and mucilage are among the principal constituents of the flowers. The flowers are gathered in the morning on sunny days, carefully dried in the sun or by artificial heat, when they are put up in bags or cedar boxes, and become ready for medicinal use. Prepared in this way, the flowers and leaves retain their properties for years, improving in their virtues by age, adding to their rich honey-like yellow coloring matter when distilled for medical purposes.
    Properties and Uses. -- This plant may rightly be regarded as a specific in all forms of pulmonary and bronchial affections. It has also great influence over the valvular action of the heart, in its healthful invigoration of the arterial and venous systems, and its wonderful power in expelling carbonic acid from the air-cells and pulmonary vessels, prior to the elimination of rich vermilion blood through the great aorta of the human economy.
    It is one of the ingredients of my "Acacian Balsam" (see page 469), which, with various other remarkable medicinal agents, forms one of the most wonderful remedies for coughs, colds, and consumption ever compounded. The plant is not much known in this country, and only imported by myself, and can consequently not be had in apothecaries.