EXOGENOUS OK DICOTYLEDONOUS PLANTS. 



465 



some ai-e pot-herbs, such as Spinach : a few are cultivated for their 

 esculent roots ; as tlie Beet, which yields sugar. Soda is extract- 

 ed from the maritime species, especially from those of Salsola and 

 Salicornia (Samphire, Glass-wort). Chenopodium anthelminticum 

 yields the well-known Worm-seed oil. 



896. Ord. AmarantaceSB {Amaranth Family). Flowers in heads, 

 spikes, or dense clusters, imbricated with dry and scarious bracts 

 which are often colored. Calyx of three to five sepals, which are 

 dry and scai-ious like the bracts. Stamens five or fewer, hypogy- 

 nous, distinct or monadelphous : anthers frequently one-celled. Utri- 

 cle often opening as a pyxis (Fig. 575). Embryo annular, always 

 vertical. Otherwise nearly as in Chenopodiaceaj. — Amarantus, 

 &c. A few Amaranths (Coxcomb, &c.) and Globe Amaranths 

 (Gomphrena) are cultivated for ornament. But most of the family 

 are coai'se and homely weeds (Pigweeds, &c.). 



897. Ord. Polygonacea (Buckwheat Family). Herbs with alter- 

 nate leaves ; remarkable for their stipules (ochreae, Fig. 305), which 



FIG. 1108. Polygonum Pennsylyanicam. 1109. Flower, laid open. 1110. Section of the 

 ovary, sliowing the erect ovule. 1111. Section of the seed, showing the embryo, at one side of 

 albumen. 



