160 



dews of night, and the fiercest rays of the noon-day sun. Soil is to them a 

 something to keep them stationary, rather than a source of nutriment, which in 

 these plants is conveyed by myriads of mouths, invisible to the naked eye, but 

 covering all their surface, to the juicy beds of cellular tissue which lie beneath 

 them. 



Properties. Refrigerant and abstergent properties, mixed sometimes with 

 a good deal of acridity, distinguish them. The fishermen of Madeira rub their 

 nets with the fresh leaves of Sempervivum glutinosum, by v hich they are ren- 

 dered as durable a;-- if fanned, provided they are steeped in some alkaline liquor. 

 Malic acid exists in Sempervivum tectorum combined with lime. Turner, 634. 



Examples. Sempervivum, Crassula, Cotyledon. 



CXLVIII. FICOIDE^ 



Ficoidejs, Juss. Gen. 315. (1789) j Diet. Sc. Nat. 16. 528. (1820) ; Dec. Prodr. 3. 415. (1828.) 



Diagnosis. Succulent polypetalous dicotyledons, with definite perigynous 

 stamens, concrete carpella, an inferior ovarium of several cells, and indefiijite 

 seeds with the embryo lying on the outside of mealy albumen. 



Anomalies. Tetragonia and Miltus have no petals, and definite seeds 

 Sesuvium and Aizoon have no petals. 



Essential Character. — Sepals definite, usually 5, but varying from 4 to 8, more or less 

 combined at the base, either cohering with the ovarium, or nearly distinct from it, equal or 

 unequal, with a quincuncial or valvate aestivation. Petals indefinite, coloured, opening- be- 

 neath bright sunshine, sometimes wanting, but in that case the inside of the calyx is coloured. 

 Stamens arising fiom the calyx, definite or indefinite, distinct; anthers oblong, incumbent. 

 Ovarium inferior, or nearly superior, many-celled; stigmata numerous, distinct. Capsule either 

 surrounded by the fleshy calyx, or naked, many-celled, often 5-celled, opening in a stellate 

 manner at the apex. Seeds definite, or more commonly indefinite, attached to me inner angle 

 of the cells; embryo lying on the outside of mealy albumen, curved or spiral. — Shrubby or her- 

 baceous plants. Leaves succulent, opposite, simple. Flowers usually terminal. 



Affinities. The embryo curved round mealy albumen, along with the 

 superior calyx, and distinctly perigynous stamens, characterizes these among 

 their neighbours, independently of their succulent habit. With Crassulacea?, 

 Chenopodeee, and Caryophyllere, they are more or less closely related. Reau- 

 murieae and Nitrariacea 3 , combined with Ficoideae by Decandolle, are families 

 different in affinity. 



Geography. The hottest sandy plains of the Cape of Good Hope nourish 

 the largest part of this order. A few are found in the south of Europe, north of 

 Africa, Chile, China, Peru, and the South Seas. 



Properties. The succulent leaves of a few are eaten, as of Tetragonia 

 expansa, Mesembryantheinum edule, and Sesuvium portulacastrum ; others 

 yield an abundance of soda. Mesembryantheinum nodiflorum is used in the 

 manufacture of Moroquin leather. 



Examples. Mesembryantheinum, Tetragonia. 





