The root of Tephrosia virginiana, Persoon (Galega virginiana, Linné).
COMMON NAMES: Turkey pea, Devil's shoestring, Goat's rue, Hoary pea, and Cat gut.
ILLUSTRATION: Meehan's Native Flowers and Ferns, Vol. I, Plate 81.
Botanical Source.—This plant is indigenous, with a perennial root, and a simple, erect, villous stem, 1 to 2 feet high. Its leaves are unequally pinnate; the leaflets numerous, 15 to 29, crowded, linear-oblong, acuminate, straight-veined, the odd one oblong-obcordate—they are about 1 inch in length by 2 or 3 lines in breadth; petiolules about 1 line long. Stipules subulate, ⅓ of an inch long, and deciduous. The flowers are large, yellowish-white, marked with red-purple, and borne in a dense, terminal, subsessile raceme. The calyx is very villous, with 5, nearly equal, subulate teeth. The banner is roundish, usually silky outside, and white; the keels obtuse, rose-colored, cohering with the red wings. Legume flat, linear, falcate, villous, and many-seeded (W.—G.).
Closely allied to this is the Tephrosia onobrychoides, Nuttall. Pilose with somewhat rusty hairs. Stem stout, erect, flexuous, more or less branched, and about 2 feet high. Leaflets 13 to 17, nearly smooth above, silky-hirsute beneath, cuneate-oblong, obtuse or retuse, and mucronate at the end, 1 inch or more long, one-fourth as wide; stipules free, subulate. The raceme is very long (1 or 2 feet), terminal, nearly opposite the leaves, and many-flowered; the flowers being small, red, and white. Calyx villose-hispid, teeth triangular, the lowest subulate, exceeding the others. Legume 2 inches long, slightly falcate, and 8 to 12-seeded (W.).
History and Description.—Each of the above plants is known in the south by the common name of Devil's shoestring. Several varieties of the plant are found growing in dry sandy soils from Canada to Florida, and from Illinois and Missouri to Texas, all of which, probably, possess similar medicinal powers. The two plants above described are the ones more commonly used. They flower in June and July. The root is of a light-drab color, from 1 ½ to 2 feet or more in length, and varying in thickness from ⅛ to ⅜ of an inch; it is crooked, not much branched, gradually tapering, with a very few scattering fibers. Internally its color is whitish-yellow. The root is hard, breaks with a short cottony fracture, as may be seen by examining the fractured end with a pocket lens, has a faint spicy odor, and a spicy, faintly sweetish and slightly astringent taste, succeeded by a moderate degree of pungency. It yields its virtues to water or alcohol. It has not been chemically examined (see Galega).
Action, Medical Uses, and Dosage.—The root of this plant alone, or in combination with other agents, has been reputed a very efficient remedy in syphilis; many southern practitioners have spoken of it to me in the highest terms as an antisyphilitic. The decoction is also much used as a vermifuge, and is said to be as efficient and powerful as spigelia. According to Dr. B. O. Jones, the plant is a mild, stimulating tonic, having a slight action on the bowels, and the secretive organs generally, and applicable in the treatment of many diseases, especially in a certain stage of typhoid fever, where there is little use of active medicine. He recommends the following compound fluid extract of tephrosia: Take of Tephrosia virginiana (the plant), 8 ounces; Rumex acutus (dock), 2 ounces; water, 4 quarts. Place the plants in the water, and boil until reduced to 1 quart. Strain, and when intended to be kept, mix with an equal bulk of brandy or diluted alcohol, and half its weight of sugar, macerate for several days, and strain through muslin. The dose is from ½ to 1 fluid ounce, 2, 3, or 4 times a day (Amer. Jour. Pharm., Vol. XXVIII, p. 218) (J. King).
Related Species.—Tephrosia Appolinea, De Candolle (Galega Appolinea, Delile). Native of Egypt, south Europe. Leaves of this species have been observed as an adulterant of senna, and are sometimes substituted for the latter. Leaflets contain indigo (Hogg).
Tephrosia purpurea, Persoon.—India. Root laxative and tonic (Dymock). T. spinosa, Persoon, has similar properties. Both are quite extensively used in India for dyspepsia and chronic diarrhoea.
Tephrosia Colonila and T. tinctoria.—Orient. Contain indigo.
Tephrosia toxicaria.—Africa, and cultivated in Jamaica. It is put into the water of streams to intoxicate fish. T. Piscatoria has similar uses.
Tephrosia leptostachya, De Candolle.—Senegambia. Leaves and root purgative.