418 MANUAL OF NATURAL HISTORY. 



shrubs, usually twining and milky ; leaves 

 alternate, undivided or lobed, exstipulate ; 

 inflorescence axillary or terminal ; calyx per- 

 sistent, in five divisions, imbricated ; corolla 

 deciduous, limb 5-lobed; aestivation plaited 

 or imbricated ; stamens five, alternate with 

 segments of corolla; ovary simple, 2-4-celled ; 

 style one ; placentae basal ; fruit 1-4-celled, 

 succulent or capsular ; cotyledons leafy, 

 doubled up. Abundant in tropical, but rare 

 in cold climes. Roots generally afford an 

 acrid juice ; yield Jalap, Scammony, Sweet 

 Potato, Oil of Rhodium, &c. 



4. Family. — Sebestens (Cordiacese). Trees; leaves 



alternate, rough, exstipulate ; flowers pani- 

 cled, bracteate ; calyx 4-5-toothed ; corolla 

 4-5-cleft, imbricated ; stamens five, free ; 

 ovary 4~8-celled ; stigma 4-8 -cleft ; fruit 

 drupaceous, 4-8-celled ; seeds exalbuminous ; 

 cotyledons leafy, plaited longitudinally. 

 Mostly tropical species in both worlds. 



5. Family. — M ilk-Weeds (Asclepiadacese). Shrubs, 



occasionally herbs, usually milky, often twin- 

 ing; leaves mostly opposite, with inter- 

 petiolary cilia in place of stipules ; flowers 

 umbelled, fascicled, or racemose ; calyx 5-di- 

 vided, persistent ; corolla 5-lobed, deciduous ; 

 aestivation imbricate, rarely valvate ; stamens 

 five ; anthers and stigma consolidated into a 

 column ; ovaries two ; fruit, two follicles, one 

 sometimes abortive ; seeds numerous ; coty- 



