388 MANUAL OF BOTANY 



equal to them in number. Ovary superior, 1- celled, with 2 

 anterior and posterior parietal placentas, very rarely meeting 

 in the centre and forming a 2-celled ovary ; style 1 ; stigmas 2. 

 Seeds small, numerous, with a minute embryo in the axis of 

 fleshy albumen. 



Division of the Order and Illustrative Genera. — The order 

 may be divided into two sub-orders as follows : — 

 Sub-order 1. Gentiane.e. — Leaves opposite, corolla imbricate- 



twisted. Illustrative Genera : — Gentiana, Linn. ; Chlora, 



Linn. 

 Sub-order 2. Menyanthe^. — Leaves alternate, corolla indupli- 



cate. Illustr. Genera : — Menyanthes, Toiirn. ; Villarsia, 



Vent. 



Distribution and Numbers. — They are found in nearly all 

 parts of the world, inhabiting both the coldest and the hottest 

 regions. There are upwards of 500 species. 



Properties and Uses. — A bitter principle almost universally 

 pervades the plants of this order ; hence many of them are tonic, 

 stomachic, and febrifugal. 



Cohort 2. — Polemoniales. 



Order 191. Polemoniace^, the Phlox Order. — Charact er. — 

 Herbs. Leaves opposite or alternate, simple or compound, 

 exstipulate. Calyx inferior, 5-partite, persistent, generally 

 regular. Corolla 5-lobed with contorted or occasionally im- 

 bricate lestivation. Stamens 5, alternate with the segments of 

 the corolla; pollen usually of a blue colour. Ovary 3-celled ; 

 style 1; stigma trifid. Fruit capsular, 3-celled, 3-valved ; ^ji?«- 

 centas axile. Seeds iew or many; embryo straight, in the axis 

 of copious horny albumen ; cotyledons ellij)tical, foliaceous. 



Distribution and Numbers. — They abound most in the tem- 

 perate parts of North and South America ; but are far less 

 abundant in Europe and Asia, and altogether unknown in 

 tropical countries. Illustrative Genera : — Phlox, Linii. ; Pole- 

 monium, Tou7'7i. ; Cobtea, Cav. There are more than 100 species. 



Properties and Uses. — Of no importance. 



Order 192. Hydrophyllace.e, the Hydrophyllum Order. — 

 Character. — Herbs, hushes, or small tr'ees. Leaves usually 

 alternate, hairy, and lobed. Flowers either solitary, stalked, 

 and axillary ; or numerous and arranged in a helicoid cyme. 

 Calyx persistent, 5-partite. Corolla regular, 5-cleft. Stamens 

 equal in number to, and alternate with, the segments of the 



