366 DROSERACEuE. POLYGALACE-E. 



tutes for Ipecacuanha. The petals of the Sweet or March Violet, the Jot, 

 of the Greeks, are laxative, and are used in the form of infusion mixed 

 with sugar ; and a violet or purple coluring matter is procured from 

 them, which is employed as a test for acids and alkalies, being changed 

 into red by the former, and into green by the latter. Viola tricolor, 

 Heart's-ease, and other species, have been used as demulcent expecto- 

 rants. V. tricolor is the origin of all the cultivated varieties of pansy. 



770. Order 19. roeraceie, the Sundew Family. (Polypet. Hypog.) 

 Sepals 5, persistent, equal; aestivation imbricated. Petals 5, hypo- 

 gynous. Stamens free, withering, alternate with the petals, or 10 or 

 more ; anthers bilocular, with longitudinal dehiscence. Ovary single ; 

 styles usually 3-5, sometimes 1 or wanting. Fruit a unilocular or 

 spuriously trilocular capsule, 3- 5-valved, with loculicidal dehiscence, 

 occasionally indehiscent. Seeds numerous, either albuminous or ex- 

 albuminous; embryo minute and erect. Herbaceous plants with 

 alternate leaves, usually inhabiting marshy places. They are found in 

 various parts of the world, in Europe, North and South America, 

 China, East Indies, &c. The order has been divided into two sections ; 

 1. Drosereae, styles 3-5, albumen present, leaves with a circulate 

 vernation, and furnished with glandular hairs ; stipules in the form of 

 fringes. 2. Parnassieas, some of the stamens sterile ; style 1 or none ; 

 no albumen nor glandular hairs. There are 8 known genera, and 

 upwards of 90 species. Examples Drosera, Aldrovanda, Dionaea, 

 Parnassia. 



771. The Droseras have a more or less acid taste, combined with 

 slight acridity. Some of them are said to be poisonous to cattle. 

 Their leaves are furnished with glandular capitate hairs, which are 

 covered with drops of fluid in sunshine ; hence the name Sundew or Eos 

 solis. An Italian liqueur, called Rossoli derives its name from a Drosera 

 used in its manufacture. Some of the Droseras have dyeing properties. 

 Dioncea muscipula, Venus's fly-trap, is a North American plant, having 

 the lamina} of the leaves in two halves, each furnished with three 

 irritable hairs, which, on being touched, cause the folding of the divi- 

 sions in an upward direction (figs. 186, 664). Aldrovanda vesiculosa, 

 an aquatic found in the south of Europe, is distinguished by its 

 whorled, cellular leaves, or floating bladders. Parnassia palustris, 

 Grass of Parnassus, has remarkable gland-like bodies between the 

 stamens (fig. 304). These are probably an abortive state of the 

 stamina! organs. Lindley looks upon them as bundles of stamens, and 

 places the genus among Hypericacese. The stamens of Parnassia are 

 irritable, and move towards the pistil in succession (*f 665). 



772. Order 20. Poiygalacete, the Milkwort Family. (Polypet. 

 Hypog.) Sepals 5, very irregular, distinct; 3 exterior, of which 1 

 is superior, and 2 inferior ; 2 interior, usually petaloid, lateral ; aesti- 

 vation imbricated. Petals hypogynous, unequal, usually 3, of which 



