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united with the upper attenuated end of the corresponding mass of pollen. 

 The parts are then in that condition in which they have been commonly 

 examined, and are exhibited in the figures of Jacquin, who, having seen them 

 only in this state, naturally considered these plants as truly gynandrous, 

 regarding the masses of pollen as the antherae, originating in ihe glands of the 

 stigma, and merely immersed in the open cells of the genuine antheras, which 

 he calls antheriferous sacs ; an opinion in which he has been followed by Rott- 

 bcell, Kcelreuter, Cavanilles, Smith, and Desfontaines. The conclusion to be 

 drawn from the observations now detailed is sufficiently obvious ; but it is 

 necessary to remark, that these observations do not entirely apply to all the 

 plants which I have referred to the Asclepiadeag ; 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 pollen coalescing 

 into masses, which are fixed or applied to processes of the stigma, in a deter- 

 minate manner ; and this is, in fact, the essential 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 commu- 

 nication, which took place in conversation, has stated it in a manner some- 

 what different from what I intended to convey to him ; for, according to his 

 statement, the pollen is projected on the stigma. The term projection, how- 

 ever, seems to imply some degree of impetus, and at the same time presents 

 the idea of something indeterminate respecting the part to which the body so 

 projected may be applied. But nothing can be more constant than the man- 

 ner in which the pollen is attached to the processes of the stigma in each 

 species." 



This 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 excessive 

 developement 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 which is confined to the leaves ; and it almost 

 disappears in Hoya, the stem of which is in the usual state, but the leaves 

 between fleshy and leathery. 



Geography. Africa must be considered as the great field of Asclepiadese, 

 especially its southern point, where vast numbers of the succulent species 

 occupy the dry and sterile places of that remarkable country. In tropical 

 India and New Holland, and in all 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 Cyanchum tomentosum and Periploca emetica ; 

 others 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. Dec. Their milk is usually acrid and bitter, and 

 is always to be suspected, although it probably participates in a slight degree 

 only in the poisonous qualities of that of Apocynere, if we can judge from the 

 use of some species as articles of food. Asclepias lactifera is said to yield so 

 sweet and copious a milk, that the Indians use it for aliment ; and Pergularia 

 edulis, Periploca esculenta, Asclepias aphylla and stipitacea, are all reported to 

 be eatable. Dec. The Cow Plant of Ceylon, or Kiriaghuna plant, Gymnema 

 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 



