DICOTYLEDONES— CALYCIFLOE^ 355 



altogether presenting a peculiar and irregular appearance. 

 Floiuers solitary, sessile. Sej^als smdjyetals imbricate, usually 

 numerous, in several whorls, and scarcely distinguishable from 

 each other, or rarely 4-merous ; adherent to die ovary {Jig, 1113). 

 Stamens numerous, with long filameiits and versatile anthers. 

 Ovary inferior, fleshy, 1-celled, with parietal placentas; style 1; 

 stigmas several. Fruit succulent. Seeds numerous, without 

 albumen. 



Distribution and Numbers. — Natives almost exclusively of 

 the tropical regions of America. Illustrative Genera: — Melo- 

 eactus, C. Bauhiri ; Mammillaria, Haiv. There are about 800 

 supposed species. 



Properties and Uses. — The fruit of many species is some- 

 what acid and agreeable, and is useful in febrile complaints. 

 The fleshy stems of the Melon Cactus (Melocactus) are eaten by 

 cattle in the dry districts of South America on account of their 

 juice. Many species of Cereus, Epipliyllum, &c., are culti- 

 vated on account of their showy flowers. Some species of Cereus, 

 as C. grandiflorus and C. nycticallus, open their flowers at 

 night ; they are remarkable for their size, some being as much 

 as 1 foot in diameter. 



Order 157. MESEMBRYANTHACEiE or FicoiDACE.E, the Ice- 

 plant Order. — Character. — Succulent herbs or shrubs, with 

 o]3posite or alternate, simple, exstipulate leaves. Calyx o — 8- 

 partite, either free or partially adherent to the ovary. Petals 

 either numerous and showy, or altogether absent. Stamens 

 perigynous or epigynous, distinct, numerous or definite. Ovary 

 inferior or nearly superior, usually many-celled, rarely 1-celled ; 

 placentas axile, free central, or parietal ; styles and stigmas as 

 many as the cells of the ovary, distinct; o^;?<?e.s usually nume- 

 rous or rarely solitary, amphitropous or anatropous. Fruit 

 usually capsular and many-celled, or rarely 1-celled, dehiscing 

 in a stellate or circumscissile manner at the apex, or splitting at 

 the base ; or woody and indehiscent. Seeds few or numerous, 

 or rarely solitary ; embryo curved or spiral, on the outside of 

 mealy albumen. 



Diagnosis. — Succulent herbs or shrubs, with simple exstipu- 

 late leaves. Sepals definite, generally more or less adherent to 

 the ovarj'. Petals very numerous or absent. Stamens perigy- 

 nous or nearly e]3igynous. Ovary inferior or nearly superior ; 

 styles distinct ; placentas axile, fi'ee central, or parietal. Fruit 

 capsular or indehiscent. Seeds with a curved or spiral embryo 

 on the outside of mealy albumen. 



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