EXOGENJE CALYCIFLOR-ffi. 131 



hardened calyx. Seed pendulous from a funiculus ; embryo 

 cylindrical, curved round farinaceous albumen. 



USES. Unknown. Mere weeds. 



TYPICAL GENUS. Scleranthus. 



74. Crassulaceee. Succulent herbs or shrubs. Stipules 

 none. Flowers usually in cymes, showy. Sepals from 3 to 

 20. Petals either distinct or cohering. Stamens inserted 

 with the petals. Hypogynous scales usually several, 1 at the 

 base of each carpel. Ovaries of the same number as the 

 petals, opposite to which they are placed. Fruit of several 

 follicles, opening on their face. Seeds variable in number. 



USES. Sempervivum tectorum, and many others, are refri- 

 gerants and somewhat acrid. Some are plants of considerable 

 beauty, and capable of growing in the most exposed and sun- 

 burnt places. Sempervivum glutinosum is used to impreg- 

 nate the water in which the fishermen of Madeira steep their 

 nets, in order to render them durable. 



TYPICAL GENERA. Sempervivum, Sedum. 



75. Mesembryacea or Ficoidea. Succulent shrubs or 

 herbs. Flowers showy, opening only under bright sunshine. 

 Sepals definite, succulent. Petals indefinite, linear. Sta- 

 mens indefinite. Ovary many-celled. Stigmas numerous. 

 Capsule many-celled, with a starry dehiscence. Embryo 

 curved or spiral, on the outside of mealy albumen. 



USES. Mesembryanthemum emarcidum, the Hottentot's 

 fig, when bruised and fermented, becomes narcotic, and is 

 used like tobacco. M. crystallinum and nodiflorum are col- 

 lected in the countries where they grow wild, for the sake of 

 the alkali they contain. 



TYPICAL GENUS. Mesembryanthemum. 



76. Cactacea. Succulent shrubs, usually destitute of leaves, 

 and with spinous buds. Flowers usually very handsome. Se- 

 pals indefinite, confounded with the petals. Stamens indefi- 

 nite ; filaments long, filiform. Ovary inferior, 1-celled, with 

 numerous parietal placentae ; stigmas numerous. Fruit succu- 

 lent. Seeds without albumen. 



USES. The fruit is eaten under the name of Indian figs. 



TYPICAL GENERA. Cereus, Mammillaria. 



K 2 



