Bidens.—Spanish Needles.

Fig. 48. Bidens frondosa. The root and seeds of Bidens bipinnata, Linné.
Nat. Ord.—Compositae.
COMMON NAME: Spanish needles.

Botanical Source and History.—Bidens bipinnata is an annual plant, with a smooth, branched stem growing from 1 to 4 feet high. The leaves are bipinnately parted, nearly smooth and petioled; the leaflets ovate-lanceolate, pinnatifid, mostly wedge-shaped at the base; the heads of flowers on slender peduncles, each with 3 or 4 obscure, obovate, yellow rays; the outer involucre of linear scales are as long as the inner, and nearly as long as the short, pale, yellow rays; the, achenia, are long and slender, 4-grooved and angled, nearly smooth, 3 or 4-awned, and adhere to the dress and to the fleece of animals (G.—W.).

This is a common plant, growing in waste places on dry soils, flowering from July to September, and found from Connecticut to Pennsylvania and westward. The root and seeds of this and the related plants below mentioned are employed medicinally, and may be used in decoction, infusion, or tincture.

Action, Medical Uses, and Dosage.—Emmenagogue and expectorant; the seeds in powder or tincture have been successfully used in amenorrhoea, dysmenorrhoea, and some other uterine derangements; and an infusion of the root has proved beneficial in severe cough. Hay asthma has recently been treated with it. Infusion freely administered.

Related Species.Bidens frondosa, Linné. Common beggar-ticks. Europe and United States This plant has a smooth, branching, rather hairy stem, from 2 to 6 feet high. Leaves 3 to 5, divided; leaflets lanceolate, pointed, coarsely-toothed, mostly stalked; outer leafy involucre much longer than the head, ciliate below; rays none; flowers in clusters at the end of the branches, yellow; achenia wedge-obovate, 2-awned, the margins ciliate with upward bristles, except near the summit. This is a common, very troublesome weed, growing in moist, cultivated fields throughout the United States; the achenia, as in the other species, adhering by their retrorsely-barbed awns to clothes, etc. It flowers from July to September (G.—W.). Bidens frondosa in infusion has cured several cases of croup, even where they have been considered beyond aid. A strong infusion of the plant, sweetened with honey, was administered to the children, warm, in doses of a tablespoonful or more every 10 or 15 minutes, until it vomited. A quantity of mucous and membranous shreds were ejected, followed by immediate relief; the children passed into a sleep, from which they awakened perfectly well. In a few hours after the emetic operation of the warm infusion, it acted as a cathartic. The leaves from which the infusion was made, were, at the same time placed in a piece of flannel with some brandy added to them, and laid over the chest and throat. This plant is also beneficial in colds, acute bronchial and laryngeal attach from exposure to cold, etc. An infusion of the seeds formed into a syrup with honey, is useful in whooping-cough. Dr. Scudder directs attention to its action on the heart and circulation, suggesting investigations in this line.

Photo: Bidens tripartita 1. Bidens connata, Willdenow (Bidens tripartita, Linné). Cuckold's, or Swamp beggar-ticks, has a smooth stem, 4-furrowed, with opposite branches, and grows from 1 to 3 feet high; the leaves are lanceolate, opposite, serrate, acuminate, slightly connate at the base; the lower ones are mostly trifid; the lateral divisions are united at the base, decurrent on the petiole; the scales of the outer involucre are longer than the head, leafy, mostly obtuse, scarcely ciliate; rays none; the achenia is narrowly wedge-form, 2, 3, or 4-awned, with downwardly-barbed margins; the flowers are terminal, solitary, consisting only of the tubular, yellow florets, surrounded by a leafy involucre. This is likewise a common weed found in wet grounds, rich fields, swamps, and ditches, from New England to Missouri. It flowers in August (G.—W.). Bidens connata has likewise been recommended in the above affections, also in palpitation of the heart, in which the infusion or decoction, drank freely through the day, has been found effectual.

Photo: Bidens cernua 1. Bidens cernua, Linné, Bur-marigold. Europe, Canada, and the United States. The leaves are subconnate, dentate, and lanceolate; the external scales are long as disk; the rays are pale yellow, few or none; the heads are cernuous (nodding). Swamps and ditches. For the uses of all three species, see also Bidens bipinnata.

King's American Dispensatory, 1898, was written by Harvey Wickes Felter, M.D., and John Uri Lloyd, Phr. M., Ph. D.