Cassia marilandica. American Senna.
Nat. Ord. — Fabaceae. Sex. Syst. — Decandria Monogynia.
Description. — Cassia Marilandica is an indigenous, perennial plant, growing from four to six feet high, with round, striated, smooth, or slightly hairy stems. The leaves are alternate, rather long, not numerous, and composed of from six to nine pairs of ovate, lanceolate, smooth, entire leaflets, green above, and yellowish-green beneath ; the common petiole is furnished at the base with a large ovate, stipitate, shining-green gland, terminating in a dark point at the top, which is sometimes double. The flowers are bright yellow, in axillary racemes, on furrowed peduncles ; the pedicels are long, glandular, and bracteate. The petals are five, concave, very obtuse and unequal, the two lower being the largest. The stamens are ten, with yellow filaments, and brown anthers, which open by a terminal pore. The three upper stamens bear short abortive anthers ; the three lowermost are long, curved, and tapering into a beak. The fruit or legume is pendulous, from two to four inches long, narrow, arcuated, mucronate, blackish, with a few scattered, reddish hairs, and containing many seeds.
History. — This plant is common to most parts of the United States, in low, moist situations, and flowering from June to the latter part of August, about which time the leaves should be collected, or in the beginning of September. Water or alcohol extracts their virtues. The leaves have a faint odor, and a nauseous taste not unlike that of the foreign senna, to which drug it is not inferior in medicinal activity. They are usually had in compressed packages from the Shakers, who cultivate the plant. Mr. Martin of Philadelphia, found the leaves to contain albumen, mucilage, starch, chlorophylle, yellow coloring matter, volatile oil, fatty matter, resin, lignin, salts of potassa and lime, and a principle analogous to cathartin.
The Cassia Chamaecrista, Prairie Senna or Partridge Pea, growing on the western prairies, is an excellent substitute for the above ; it is likewise known as Dwarf Cassia and Sensitive Pea.
Properties and Uses. — A safe and efficient cathartic, equal to the imported article, for which it may be substituted. But, owing to the presence of argel leaves, the foreign senna has its activity increased, hence, in giving the American article, the dose will be one-third larger than of the other. Its most convenient form of administration is that of infusion, which should be combined with articles similar to the infusion of imported senna, in order to obviate any tendency to griping. The dose in powder is from half a drachm to two and a half drachms. The infusion may be made by adding one ounce of the leaves, with a drachm of coriander seeds, to a pint of boiling water. Macerate for an hour in a covered vessel, and strain ; dose, four or five fluidounces.