350 MANUAL OF BOTANY 



Properties and Uses. — Some species of Homalium are astrin- 

 gent, but nothing is known of the properties of the other 

 genera. 



Order 148. LoASACEiE, the ChiH Nettle Order. — Character. 

 Herbaceous i^lants, with stiff hairs or stinging glands. Leaves 

 exstipnlate. Calyx superior, 4- or 5-parted, persistent. Petals 

 5 or 10, in 2 whorls, often hooded. Stamens numerous, in 

 several whorls, either distinct or united in bundles. Ovary 

 inferior, 1- celled, with several parietal placentas, or 1 axile pla- 

 centa ; style 1 ; ovules anatropous. Fruit capsular or succulent. 

 Seeds with a loose testa, and having an embryo lying in the 

 axis of fleshy albumen. 



Distrihution and Numbers. — They are all natives of North 

 and South iVmerica. Illustrative Genera : — Bartonia, Muelil. ; 

 Loasa, Adans. There are about 70 species. 



Properties and Uses. — Some of the species are remarkable 

 for their stinging glands ; hence their common name of Chili 

 Nettles. Several species are cultivated on account of the beauty 

 of their flowers. A Mexican species, Mentzelia liispida, is re- 

 puted to possess a purgative root. 



Order 149. Turnerace^, the Tiu-nera Order. — Charac- 

 ter. — Herbaceous or somewhat sliruhby plants. Leaves alter- 

 nate, exstipulate, hairy. Floiuers axillary. Calyx inferior, 5- 

 lobed, imbricate in aestivation. Petals 5, equal, twisted in aesti- 

 vation, without a corona, perigynous, deciduous. Stamens 5, 

 alternate with the petals, ^eYi^jnou^; filaments distinct. Ovary 

 1 -celled, superior, with 3 parietal placentas; styles 3, more or 

 less united at the base, forked or branched above. Fruit cap- 

 sular, 1 -celled, 3-valved, partially dehiscing in a loculicidal 

 manner. Seeds with a caruncle on one side, and a slightly 

 curved embryo in the midst of fleshy albumen. 



Distribution and Numhers. — Natives exclusively of South 

 America and the West Indies. Illustrative Genera : — Turnera, 

 Plum.', Piriqueta, J.?^6?. There are about 60 species. 



Properties and Uses. — Some are said to be astringent, others 

 tonic and expectorant, and a few aromatic. 



Order 150. Passiflorace^, the Passion-flower Order. — Cha- 

 racter. — Herbs or shrubs, usually climbing by tendrils, or 

 rarely trees. Leaves alternate, with foliaceous or rarely minute 

 stipules. Flowers perfect or very rarely unisexual. Sepals 5, 

 united below into a tube, the throat of which bears a number 

 of filamentous processes, thus forming a kind of corona ; 

 petals 5, inserted into the threat of the calyx on the outside 



