CASSIA SENNA. 
129 
Senna is an annual plant, a native of Asia, and grows sponta- 
neously in Egypt, Syria, and some parts of Arabia, especially about 
Mocha; it is cultivated in some of the West India Islands, and also 
in the south of France. Senna was first cultivated in England 
about the year 1640; but the temperature of our climate is too cold 
for this tender exotic, which will not produce flowers unless the 
seeds are sown in a good hot-bed.* 
This species of Senna rises to the height of about two feet ; the 
stem is rather woody, erect, and branching ; the leaves grow alter- 
nate, are doubly pinnate, smooth, flat, and furnished at their base 
with two narrow, pointed stipules ; each leaf is composed of from 
five to six pair of leaflets, about an inch long, and about one fourth 
the breadtli ; the leaflets are oval, pointed, entire, sessile, and of a 
yellow green colour ; the flowers grow in loose axillary racemes, 
towards the upper part of the stems ; the calyx is monophyllous, 
five toothed : the teeth are obtuse, somewhat concave, and deci- 
duous ; the corolla consists of five, roundish, entire, concave petals, 
the three lower ones the largest ; the filaments are ten, the three 
inferior longer than the others ; the anthers are large and curved ; 
germen cylindrical ; style short, incurved, and supports obtuse 
stigmata; the fruit is an ovate, membranous legume, with folia- 
ceous appendages, marked with transverse striae ; bivalve, with six or 
nine cells, and divided by very thin transverse partitions, each 
containing one heart-shaped, oblong seed. 
Three sorts of Senna are imported and sold in the English mar- 
kets, under the names of Alexandrian, Tripolinn, and East Indian ; f 
the first is the produce of Egypt, called in Nubia guebelly, where 
it grows wild ; this is the pointed-leaved Senna, which, when 
carefully dried, has a faint, rather sickly odour, and a slightly 
bitter, sweetish, and nauseous taste. This sort of Senna is the 
most purgative, and is rendered still more so by the leaves of the 
coronilla emerus, and periploca graeca, with which it is frequently 
adulterated ; these however may be detected by being larger and 
more pointed than the true Senna. The Tripolian is a variety of the 
Alexandrian. We are told by Dr. Ainslie that the East India 
* The Senna of commerce consists of tlie leaves of several varieties of this plant ; that 
known by the name of Alexandrian Senna has derived its name from the port of Alex- 
andria, the great mart for the exportation of Senna from Egypt, Arabia, &c. 
+ This last, according to Lemaire Lisancourt, is the produce of a species of Senna 
which grows on the west coast of Africa, near Sierra Leone, and over the country of 
Senegambia ; and to which be has given the name of Cassia Elongata. Ed, 
VOL. I. S 
