258 



MEDICAL BOTANY. 



Legume and leaflet of C. medica, var. lanceolata. Do. do. of 

 C. obovata. 



remarks on the subject, by Dr. J. Carson, will be found in the American 

 Journal of Pharmacy, ii. 178. 



Fortunately, this confusion does not exist in any great degree in the Sennas 

 of commerce, which are divided into many kinds, designated by the names 

 of the places at which they are grown, or from which they are imported. 



Senna is brought from the different Mediterranean ports, and from India ; 

 much of the East Indian comes to this country by way of London. Nume- 

 rous varieties have been described, but they may be reduced to three : — the 

 Alexandrian, the East Indian, and the Tripoli. 



Alexandrian. — This comes from the Egyptian and other Mediterranean 



ports, and consists 

 Fi s- 132 * not only of the leaves 



of the acute-leaved 

 Cassias, but also of 

 those of C. obovata, 

 and is always adul- 

 terated with leaves 

 and flowers of So- 

 lenostemma argel, 

 sometimes with those 

 of Tephrosia apolli- 

 nea. Mr. Landerer 

 states that it is chiefly 

 brought from Upper 

 Egypt, Nubia, Sen- 

 naar, &c, and is 

 always obtained from 

 wild plants. The har- 

 vest commences in September, when the branches of the shrub are cut, and 

 exposed to the sun, until the leaves begin to fade. They are then collected 

 into bundles, and placed on rocks and high grounds, so as to have the full 

 benefit of the sun's rays and the air. When the leaves are quite dry, the 

 branches are laid in heaps, and threshed until the leaves are separated from 

 them. These not being broken or mixed with twigs and dirt, are the most 

 prized. The leaves not being all detached by this means, the bundles are 

 placed on a clay floor, and camels driven over them, till no more leaves 

 remain attached. This process breaks them much, and they become 

 mixed with portions of twigs, &c. The Senna thus collected in various 

 places is packed in sacks, and conveyed to the Nile, where it is transferred 

 to boats and carried to Cairo and Alexandria, where it is unpacked, sorted, 

 and repacked in large bales. He further states, that the adulteration of Senna 

 is not practised intentionally. (Amer. Jour. Pharm. xii. 74.) This latter 

 assertion is widely different from that of other authors, who state that the ad- 

 mixture takes place at the various entrepots on the Nile, where the Senna 

 is received from the caravans. ■ Rouillure (Ann. de Chim. lvi. 161) says 

 that at Boulak, the proportions of the different leaves are, 500 parts of acute 

 leaves to 300 of obtuse and 200 of Argel leaves. 



As found in the shops, this kind of Senna is of a grayish-green colour, 

 with an odour somewhat resembling that of tea, and an unpleasant, viscid 

 taste. It presents a broken appearance, and consists of the leaves, flowers, 

 and fruits of the above-mentioned plants, and various impurities. The Argel 

 leaves and flowers may readily be recognised from those of Senna; the first 

 by their paler colour, thicker and more coriaceous texture, by their being 

 equilateral, and the imperfect developement of their lateral veins ; the flowers 

 by being in corymbs. Dr. Pereira states that in some bales, Argel flowers 



