Asclepiada'ceæ

Asclepiada'ceæ (or Asclepiadææ), a chiefly tropical order of corollifloral dicotyledons, closely allied to Apocynaceæ, from which they are chiefly distinguished by the united filaments and coherent stigmas to which the anthers adhere, as well as by the peculiar orchid-like pollen-masses. They are mostly shrubs, often with twining stems, and almost always possess milky juice, which is usually poisonous, sometimes so much so as to be used for arrow-points, but is occasionally bland, and even in the case of the Cow-plant of Ceylon (Gymnema lactifera) is used as food. It is sometimes also a source of caoutchouc. Some are prized by florists, notably the fragrant Stephanotis, the Wax-plant (Hoya carnosa), as well as species of the curious genus Ceropogia, and the cactus-like and carrion-scented Stapelia. A number of species are medicinal, as Indian Sarsaparilla (Hæmidemus indicus); Mudar (Calotropis gigantea), so highly prized in the East Indies; Surcostemma glaucum, the Ipecacuanha of Venezuela; Tylophora asth- matica and Secamone emetica, the roots of which are used as emetics, and in smaller doses as cathartics, and the former of which is employed as Ipecacuanha in India. Cynanchum acutum, which yields a purgative called Montpelier Scammony, and Vincetoxicum officinale, which possesses similar properties. Argel (q.v.), much used for adulterating senna, belongs to this order.—The down of the seeds is sometimes employed as a substitute for silk or cotton; and the stems of not a few species afford useful fibres, as those of the Asclepias syriaca, the Mudar and other species of Calotropis, natives of India and Persia, Hoya viridiflora, Holostemma Rheedianum, &c. The Mudar or Yercum fibre is highly spoken of, and the bark of Marsdenia tenacissima, a small climbing-plant, yields a fibre called Jetee, of which the Rajmahal mountaineers make bowstrings of remarkable elasticity. The fibre of M. Roylei is used in Nepal. Ornithanthera viminea, which grows at the base of the Himalayas, and has long leafless wand-like stems of 10 feet in height, yields a fibre of remarkable length and tenacity, suited for rope-making. The fibres of other species are used in Sindh for making the ropes and bands used in wells, as water does not rot them. A few species, as Marsdenia tinctoria, a native of Silhet, yield indigo of excellent quality. There are many species native in North America.