SennAe Folia. The Leaves of Cassia Lanceolata, C. Obovata, Cassia Elongata, and of other species of Cassia. Nat. Ord. Caesalpineae. Linn. Syst. Decandria Monogynia. There are five principal kinds of Senna met with in commerce, named after their respective sources. They rank in activity and value in the following order: - 1, Alexandrian Senna (offic.); 2, Tinnevelly or Madras (offic.); 3, Bombay or Common Indian Senna; 4, Tripoli; and 5, Aleppo. An excellent description of these varieties (which differ much in form, &c.) will be found in Prof. Royle's Manual, and in Dr. Pereira's larger work.

Med. Prop. and Action. Cathartic. It is chiefly given in infusion, in doses of fl. oz. j. - fl. oz. ij., in conjunction with a saline purgative, forming the common "Black Draught." The confection, in doses of gr. lx. - oz. ss., is also a useful, mild purgative; and the tincture (fl. drm. j. - fl. drs. iij.) is a warm, aromatic purge, but chiefly used as an adjunct to other remedies of the same class. The activity of Senna was for a long time considered to reside in a peculiar principle, Cathartine; but M. Heerlein has shown this opinion to be incorrect. In his own person, iv. of this substance, taken in four doses, at the intervals of an hour, produced no sensible effect. Senna acts principally on the small intestines, and produces copious, loose evacuations. It appears to act, according to Drs. Ballard and Garrod, both by augmenting the peri-staltic movements, and by favouring the flow of the intestinal secretions. It generally operates under four hours, and in some persons its operation is attended with griping; this may be in a great measure obviated by combining it with carminatives. Its efficacy is increased by drinking plentifully of diluents, by the addition of Camphor, or of the decoction of Guaiacum; also by the sulphates of Magnesia and Soda, and some other saline purgatives. Its efficacy is decreased or destroyed by boiling, by being kept long ready-made, by the carbonates of alkalies, and by Rhubarb. Its nauseous taste is disguised by giving it in strong coffee, or by the addition of milk and sugar, when it much resembles common tea. The administration of Senna is attended with very slight, if any, consequent constipation; and if taken habitually, as in the case of Castor Oil, the dose may gradually be decreased until a very small quantity suffices to procure a full evacuation. That it exercises a specific action on the bowels is shown by the experiments of Petit, * who found fomentations of Senna leaves placed over the abdomen produce a brisk cathartic operation. If given to a woman during lactation, it communicates a purgative property to the milk.

* Brit. For. Med. Rev., No. i p. 265.

Mat. Med., art. Senega.

Offic. Prep. 1. Confectio SennAe (Senna in fine powder oz. vij.; Coriander in fine powdor oz. iij.; Figs oz. xij.; Tamarinds oz. ix.; Cassia Pulp oz. ix.; Prunes oz. vj.; Extract of Liquorice oz. 3/4; Refined Sugar oz. xxx.; Distilled Water fl. oz. xxiv. Prepared by boiling the Figs in the Water for four hours; then expressing and straining the liquor, to which more water is to be added, to make it fl. oz. xxiv. The Prunes are then boiled in it for four hours. The Tamarinds and Cassia are then added, macerated for a short time, and the pulp is pressed through a hair sieve. The Sugar and liquorice are then dissolved in the mixture with a gentle heat, and while it is still warm the Senna and Coriander are added, and thoroughly combined by stirring. The product should weigh oz. lx.). Commonly known as "Lenitive Electuary." Dose, gr. lx. - oz. ss.