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in the glands of the stigma, and merely immersed in the open cells of the 
genuine antherse, which he calls antheriferous sacs ; an opinion in which he 
has been followed by Rottboell, Koelreuter, Cavanilles, Smith, and Desfon- 
taines. The conclusion to be drawn from the observations now detailed is 
sufficiently obvious ; but it is necessary to remark, that these obseiwations do 
not entirely apply to all the plants which I have referred to the Asclepiadese ; 
some of them, especially Periploca, having a granular pollen, applied in a 
very different manner to the glands of the stigma ; they all, however, agree 
in having poUen coalescing into masses, which are fixed or applied to pro- 
cesses of the stigma, in a determinate manner ; and this is, in fact, the essen- 
tial character of the order. Dr. Smith, in the second edition of his valuable 
Introduction to Botany, has noticed my opinion on this subject : but, probably 
from an indistinctness in the communication, which took place in conversa- 
tion, has stated it in a manner somewhat different from what I intended to 
convey it to him ; for, according to his statement, the pollen is projected on 
the stigma. Tlie term projection, however, seems to imply some degree of 
impetus, and at the same time presents the idea of something indeterminate 
respecting the part to wffiich the body so projected may be applied. But no- 
thing can be more constant than the manner in which the pollen is attached 
to the process of the stigma in each species.” 
Tlie order is one of those which contain indifferently what are called suc- 
culent plants and such as are in the usual state of other plants ; this exces- 
sive development of the cellular tissue of the stem, and reduction of that of 
the leaves, is in its greatest degree in Stapelia and Ceropegia ; it is diminished 
in Dischidia, the succulence of wffiich is confined to the leaves ; and it almost 
disappears in Hoya, the stem of which is in the usual state, but the leaves be- 
tween fleshy and leathery. 
Geography. Africa must be considered as the gi-eat field of Asclepiada- 
cese, especially its southern point, where vast numbers of the succulent species 
occupy the dry and sterile places of that remarkable country. In tropical In- 
dia and New Holland, and in aU the equinoctial parts of America, they all 
abound. Two genera only are found in northern latitudes, one of which, As- 
clepias, abounds in species, and is confined apparently to the eastern side of 
North America; the other, Cynanchum, is remarkable for extending from 59° 
north latitude to 32° south latitude. 
Properties. The roots are generally acrid and stimulating, whence some 
of them act as emetics, as C}Tianchum tomentosum and Periploca emetica ; 
nthers are diaphoretic and sudorific, as the purgative Asclepias decumbens, 
which has the singular property of exciting general perspiration without in- 
creasing in any perceptible degree the heat of the body ; it is constantly used 
in Virginia against pleurisy. DC. Their milk is usually acrid and bitter, 
and is always to be suspected, although it probably participates in a shght de- 
gree only in the poisonous qualities of that of Apocynaceee, if we can judge from 
the use of some species as articles of food. Asclepias lactifera is said to yield 
so sw^eet and copious a milk, that the Indians use it for ahment ; and Pergula- 
ria edulis, Periploca esculenta, Asclepias aphylla and stipitacea, are all re- 
ported to be eatable. DC. The Cow Plant of Ceylon, or Kiriaghuna plant, 
Gjunnema lactiferum, yields a milk of which the Cingalese make use for food ; 
its leaves are also used when boiled. But very little is known about the real 
qualities of such plants. The root and tender stalks of Asclepias volubilis L. 
sicken and excite expectoration. Ainslie,^. 154. Asclepias tuberosa, or But- 
terfly weed, is a popular remedy in the United States for a variety of disor- 
ders ; its properties seem be those of a mild cathartic, and of a certain diapho- 
retic attended with no inconsiderable expectorant effect. Barton, 1. 244. 
The root of Diplolepis vomitoria has a bitterish and somewhat nauseous taste. 
