EXOGENOUS OK DICOTYLEDONOUS PLANTS. 



397 



with few or numerous seeds, attached to a central basilar placenta, 

 often by slender funiculi. Seed and embryo as in CaryophyllaceiB. 

 — Ex. Portulaca (Purslane, Fig. 389, 588) Claytonia. Chiefly 

 natives of dry places in the warmer parts of the world ; except 

 Claytonia. Insipid or slightly bitter : several are pot-herbs, as the 

 Purslane. Some are ornamental. The farinaceous root of Lewisia 



rediviva, a native of the dry interior plains of Oregon, is an impor- 

 tant article of food with the natives. 



770. Ord. Mesembryanthemacca; {Fig-Marigold Family) consists of 



succulent plants, with showy flowers opening only under bright sun- 

 shine, containing an indefinite number of petals and stamens, and a 

 many-celled and many-seeded capsule : otherwise much as in Caryo- 

 phyllaceEB. — -Ex. Mesembryanthemum (Fig-Marigold, Ice-plant); 

 chiefly natives of the Cape of Good Hope, flourishing in the most 

 arid situations. 



771. Ord. lalvaceEC {Mallow Family). Herbs, shrubs, or rarely 

 trees. Leaves alternate, palmately veined, with stipules. Flowers 

 ■regular, often with an involucel, forming a double calyx. Calyx 

 mostly of five sepals, more or less united at the base, valvate in 



FIG. 728. Flower of the Purslane ; the calyx cut away at the point where it adheres to the 

 ovary, and laid open. 729. A capsule (pyxis) of the same, transversely dehiscent. 730. Clay- 

 tonia Virginica (Spring-Beauty). 731. Diagram of the flower. 732. Young fruit and the per- 

 sistent two-leaved calyx. 733. Section of the dehiscing capsule. 734. A seed. 735. The- 

 same, vertically divided. 736. The embryo, detached. 



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