TAUT II.

Materia Mewca, — Cassia Senna.

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2. Cassia Senna.Officinal. Sennje folia, Lond. Folia cassls: senn/E, Edin.Senna; Folia. Dub. Senna leaves.

St/n Sene (F.), Sennablater (G.), Senna (/.), Sena(G), Sena {Arab.), SenaMecci(.ff.).

This species of cassia, which yields the senna of commerce,is an annual plant, a native of Upper Egypt. The best growsin the valleys of Nubia', where it is named Abyreyga ; flow-ering in July and August. It rises with an erect branching-stem about two feet in height. At the base of the leaves, whichare pinnate, and placed in alternate order, are two narrowpointed stipules : the leaflets, of which each leaf has five or sixpair, are sessile, oblique at the base, oval, pointed, scarcelyan inch in length, and one-fourth of an inch broad, and of ayellowish green colour. The flowers are yellow, in loose axil-lary spikes: the calyx is deciduous, consisting of five narrow,obtuse, concave leaflets ; the petals are roundish, concave, en-tire ; the three lower ones larger than the two upper: theundermost filaments also are longer than the others, and fur-nished with large rostrated curved anthers ; and the gevmen islong and flat, with a short incurved style terminated by an ob-tuse stigma. The fruit is an ovate, reniform, membranous,leafy, compressed legume, torose and marked with capillary,transverse, parallel strias : bivalve, with six or nine cells, divi-ded by very thin transverse partitions, and each containing oneoblong heart-shaped seed. 2

The best senna, named in Nubia guebelly, or sena meklce,grows wild, and yields two crops of leaves, the abundance ofwhich depends on the periodical rains. The first crop is col-lected after the first rains about the middle of September ; thesecond in the following March, at which time the fruit is at itsfull maturity. The plants are cut when the flowers begin tofall, and exposed on the rocks to dry in the sun.'—The leavesare then picked, packed up in bales, and sent to Boulac, thegreat entrepot of senna, where they are mixed with two otherspecies of cassia; one the C. senna of Forskal with obtuseleaves; the other probably the C. angnstifolia of Willdenow,the leaves of which are longer, narrower, and sharper pointedthan those of the proper senna, and come from Mocha; butthe leaf with which senna is chiefly adulterated is that of theCynanchum Oleqfolium, known in Egypt by the name of Argelor Arguel. The proportions, according to Dr. Calloden are fivehundred parts lance-leafed senna, two hundred of obovate senna,and two hundred of argel.

The two first are equally good, but

1 C. Nectoux. Vide Phil. Mag. xv. .55. 2 Gartner tie Fruct. ii. 312. (. 146.

1 Burckhardt says that the Bedouin Arabs, who are the chief collectors of senna,sell it to the merchants of Esne at about one pound sterling per camel load (from100 to jOO weight.) Travels in Nubia, 4to. p. 31.

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