162 



MEDICAL BOTANY. 



tivated on account of its roots, which are much employed there for medicinal 

 purposes. These, as found in the shops, are in pieces of three or four inches 

 in length, about the thickness of the finger, of a white colour externally, 

 owing to the removal of the grayish-yellow epidermis. They possess 

 scarcely any odour, and have a vapid, mucilaginous taste. They have 

 often been analyzed, with nearly similar results, namely, a large proportion 

 of mucilage, fecula, inuline, &c. Mr. Bacon discovered what he thought to 

 be a new principle in them, on which he bestowed the name of Altheine, but 

 subsequent researches have shown that it is identical with asparagine. 



Medical Properties, SfC. — The Marsh-mallow is very generally used in 

 Europe as a demulcent and emollient, but in this country its employment is 

 very limited, its place being supplied by other articles of equal efficacy, which 

 are more readily procurable, and especially by the bark of the Slippery Elm. 

 It would be superfluous to advert to the various preparations of this article 

 and their applications ; it is sufficient to state, that externally, it is employed 

 in fomentations, baths, and cataplasms, and internally, in infusion, syrup, and 

 in a conserve that enjoys a high reputation as a demulcent in irritations and 

 inflammations of the respiratory organs. The powder is also used to give 

 consistence to many pharmaceutical preparations. As almost all the Mal- 

 vaceae possess the same mucilaginous properties, several of them are advan- 

 tageously substituted for the Marsh-mallow, some of them, in fact, present 

 much higher claims to notice, particularly the Abelmoschus esculentus, or Okra, 

 which abounds in a bland mucilage that might be advantageously employed 

 as an emollient in many of the phlegmasia^. 



The flowers of the A. rosea, are used in Greece for the same purposes as 

 those of the Marsh-mallow, and the leaves are said to yield a blue colouring 

 matter analogous to indigo. 



Gossypium. — Linn. 



Calyx cup-shaped, obtusely 5-toothed, with a three-leavel involucel, with the leaves 

 united and cordate at base, and irregularly dentate and incised ; stigmas 3-5. Capsules 

 3-5-celled, loculicidal. Seeds numerous, embedded in cotton. 



This highly interesting and important genus consists of several species, 

 but the best botanical authorities differ as to the exact number. De Candolle 

 admits of thirteen, and many more are enumerated by other writers. Dr. 

 Hamilton, who is followed by Wight and Arnott, is of opinion that there are 

 but two, the G. album, with white seeds, and the G. nigrum, with black seeds. 

 Cultivation has produced so many changes that it is now difficult to decide as 

 to the propriety of thus limiting or extending the species. In all of them the 

 young branches and leaves are more or less marked with black dots, and the 

 nervures of the lower surface of the leaves furnished with one or more glands. 

 They are natives of the tropical regions of Asia and America. 



G. herbaceum, Linn. — Leaves 3-5 lobed, with a single gland below, lobes mucronate. 

 Seeds free, covered with a short tomentum under the long white cotton. 



Linn., Sp. PI. 845 ; De Candolle, Prod. i. 456 ; Roxburgh, Fl. Ind. iii. 

 184 ; Torrey and Gray, Fl. i. 230. 



Common Name. — Cotton Plant. 



Foreign Names. — Cotonnier, Fr. ; Bambagia, Cotone, It. ; Krautargige 

 baumevolle, Ger. 



Description. — A shrub which is about three or four feet high, with a round, upright 

 pubescent stem, brown at the lower part, with straight fissures, spotted with black at the 

 top, the branches are spreading. The leaves arc five-lobed, with a single gland below. 

 The calyx is cup-shaped, obtusely five-toothed, and surrounded by a tbree-leaved invo- 

 lucel, the leaflets of which are much cut and dentate. The corolla is composed of five 

 spreading petals united below into a tube, of a pale yellow colour, with a red spot on each 



