DICOTYLEDONES— COEOLLIFLOEtE 



385 



stigma, 2-celled ; pollen granular. Ovary composed of 2 carpels, 

 which are generally merely in contact, but sometimes united so 

 as to form a 2-celled or more rarely a 1 -celled ovary ; styles 2 

 or 1 ; stigma 1, expanded at the base and apex, and contracted 

 in the middle, so as to resemble in form an hom^-glass or dumb- 

 bell; ovules numerous. Fruit consisting of 1 or 2 follicles, or 

 a capsule, drupe, or berry. Seeds usually with albumen, or 

 rarely exalbuminous, often comose. 



Distribution and Numbers. — Natives principal!}^ of the 

 tropics, but a few occur in northern regions. Vinca is the 

 only British genus. Illustrative Genera : — Allamanda, Linn. ; 

 Urceola, Boxb. ; Apocyniun, Tourn. There are about 600 

 species. 



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



Fig. 1151. 



Fig. 1152. 



/'/;/. 1151. Vertical section of the 

 flower of Periwinkle (Vhica). 



Fkj. 1152. Diagi-am of the 



flower of the same. 



to be suspected, as many of them are intenselj' poisonous, 

 although the fruits of a few species are edible. Some are 

 drastic purgatives, and of others the bark is tonic and febri- 

 fugal. India-rubber or Caoutchouc, now commonly known in 

 commerce as Rubber, is obtained from the milky juice of several 

 species. 



Order 188. Asclepiadace^, the Asclepias Order. — Cliarac- 

 ter. — Shrubs or herbs, commonly milky, frequently twining 

 and sometimes succulent. Leaves entire, opposite or whorled, 

 or rarely scattered, exstipulate. Flowers regular. Calyx and 

 corolla 5-partite ; lestivation of the latter imbricate or rarely 

 valvate ; the calyx persistent, the corolla deciduous. Stamens 5, 

 alternate with the lobes of the corolla; filaments usually 

 combined so as to form a tube round the pistil, or sometimes 

 distinct; «?zf7«ers frequently having pouch -shaped and hornlike 



VOL. II. c c 



