458 SYSTEMATIC BOTANY. 



base ifig. 870). Ovary 1-celled, with 3 parietal placentas {fig, 

 775); style single, usually declinate {fig. 429); stigma capitate, 

 oblique, hooded {fig. 870, st) ; ovules usually numerous ( fig. 

 429, 0, o). Fruit capsular, 3-valved {fig. 665), dehiscence loculi- 

 cidal ; placentas on the middle of the valves. Seeds usually nu- 

 merous {fig. 665), sometimes definite ; embryo straight, erect, iu 

 the axis of fleshy albumen {fig. 871). 



Diagnosis. — Herbs or shrubs. Leaves simple, stipulate, and 

 with involute vernation. Flowers regular or irregular. Sepals, 

 petals, and stamens, 5 each, hypogynous. Stamens all perfect; 

 anthers introrse with the filaments prolonged beyond them. 

 Ovary 1-celled, with 3 parietal placentas opposite the 3 outer 

 sepals; style and stigma single. Fruit 1-celled, dehiscing by 3 

 valves, each valve bearing a placenta in its middle. Seeds 

 having a straight erect embryo in the axis of fleshy albumen. 



Division of the Order, and Examples of the Genera, — The order 

 has been divided into two sub-orders as follows: — 

 Sub-order 1. Violece. — Having irregular flowers, and appen- 



daged anthers. Examples: — Viola, lonidium. 

 Sub-order 2. Alsodece. — With regular flowers, and anthers not fur- 

 nished with appendages. Examples : — Alsodeia, Pentaloba. 

 Distribution and Numbers. — The herbaceous plants of the sub- 

 order Violeai are chiefly natives of Europe, Siberia, and North 

 America; the shrubby mostly of South America. The AlsodejB 

 are exclusively natives of South America, Africa, and Malacca. 

 There are 1 5 genera, and about 300 species belonging to the 

 order Violacete. 



Properties and Uses. — The plants of this order are chiefly 

 remarkable for emetic and purgative properties. A few also are 

 mucilaginous, and others have been rc])uted anodyne. The 

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

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

 principle of the true Ipecacuanha root. This principle is more 

 especially found in some of the shrubby South American species, 

 but 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 iu this country. The following are the 

 more important : — 



Viola odorata, the March or Sweet Violet.— The flowers of this plant 

 have been always liighly esteemed for their fragrance. An infusion or syrup 

 of the petals is a nseiiil chemical test, as the violet or purplish colour is 

 chanf^ed into red by acids, and green by alkalies. The syrup is officinal, and 

 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 contain violine. Viola canina, the Dog Violet, is said to be very ettica- 

 cious in cutaneous diseases. Viula tricolor, a common indigenous plant, is the 

 origin of all our cultivated varieties of Pansies or Ileart's-ease. The Violets 

 generally, have been used on the Continent, as demulcent expectorants. 



lonidium Ipecacuanha, Woody Ipecacujinha The root of this plant was 



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



