THALAMIFLOKJE. 449 



mucilaginous, and others hare been reputed to be anodyne. The 

 emetic property is due to a peculiar alkaloid named vioUa, which 

 greatly resembles, if it be not identical with, emetia, the active 

 principle of the true Ipecacuanha root. This principle is more 

 especially found in some of the shrubby South American species, 

 ]jut it also occurs, to some extent at least, in many of the herba- 

 ceous European species. The plants of this order deserve further 

 trial as medicinal agents in this country. The following are the 

 more important: — 



lonidium. — The root of 7. Ipecacuanha, Voody Ipecacuanha, ■was supposed 

 by Linnfeus to be the source of the true Ipecacuanha. It is the false 

 Ipecacuanha of Brazil, and is employed as an emetic in that region. It 

 contains eniptia. Other species of lonidium, as /. parviflorum, I. Itubi/. S:c., 

 ]wssess similar properties. The roots of /. pat-viflorum (/. microphyllum, 

 Hnmb. <t Dec.) constitute the Cuchnnchully de Cuenga, which is much used 

 in the province of Venezuela as a remedy for elephantiasis. 



Fio/a.— The fiowers of V. odorata, the" March or Sweet Violet, have been 

 always highly esteemed for their fr.-igrance. An infusion or syrup of the 

 petals is a useful chemical test, as the violet or purplish colour is changed 

 into red by acids, and green by alkalies. The syrup is employed partly on 

 account of its colour and odour, but chiefly as a laxative for very young 

 children. The flowers were formerly regarded as anodyne. The roots, 

 stems, and seeds have been also regarded as emetic and purgative. They 

 contaiu vioUa. Viola canina, the Dog Violet, is said to be efficacious in 

 certain cutaneous diseases, llola tricolor, a common indigenous plant, is 

 the origin of all our cultivated varieties of Pansies or Heart's-ease. The 

 Violets" generally have been used on the Continent, as demulcent expecto- 

 rants. 



Natural Order 21. SAuvAGBSiACKa:. — The Sauvagesia Order. 

 —Character. — This order is by some botanists considered 

 as merely a sub-order of Violacese. It is distinguished by its 

 plants having either 5 perfect stamens alternate with 5 sterile 

 ones, or numerous stamens ; if only 5, these are also opposite 

 the petals ; the anthers are also extrorse, and have no appen- 

 <lages. The fruit also bursts septicidally, and hence each valve 

 i>ears the placentas at its margins. 



Distribution, ^c. — They are natives chiefly of South Ame- 

 rica and the "West Indies. ExampUs of the Genera : — Sauvagesia, 

 Lavradia. Lindley enumerates 1 5 species. 



Fro pert is and tfscs. — But little is known of the properties of 

 the plants in this order. Sauvagesia erccta contains a good deal 

 of mucilaginous matter, and has been used internally as a diu- 

 retic, and in inflammation of the bowels, and also externally in 

 diseases of the eye. 



Natural Order 22. DEOSEEACEiE. — The Sun-dew Order. — 

 Character. — Herbaceous plants growing in boggy or marshy 

 place:;, frequently glandular. Leaves alternate, fringed at their 

 base {fg. 349), and with a circinate vernation. Peduncles, 

 when yotmg, circinate. Sepals and petals o, hypogynous, equal, 

 imbricate, persistent. Stametis as many as the petals and alter- 

 nate with them, or twice, thrice, or four times as many, distinct, 



G G 



