CLASSIFICATION OF ANGIOSPERMS. 531 



bryanthemum as well as other members of this family are edible, 

 and the leaves of some species are used as vegetables like lettuce. 



/. PORTULACACE^E. The plants are fleshy or succulent 

 herbs mostly indigenous to America. The two common represen- 

 tatives are the spring beauty (Claytonia virginica), the tubers of 

 which are rich in starch, and purslane (Portulaca oleracea), some- 

 times used .as a green vegetable. The seeds of the latter plant as 

 well as of other species of Portulaca are used in medicine. 



g. CARYOPHYLLACE^. The plants are annual or peren- 

 nial herbs, often swollen at the nodes, with opposite, entire leaves, 

 and usually perfect regular flowers. The perianth has a distinct 

 corolla of 4 or 5 petals. The fruit is a capsule and the seeds are 

 half anatropous. The plants are most abundant in the northern 

 hemisphere ; and some of them are quite showy, as the CARNATION 

 (Dianthus caryophyllus} and pinks (Dianthus species) and the 

 cultivated pink or Sweet William (D. barbatus). A number of 

 the members of this group contain saponin, as Bouncing Bet 

 (Saponaria officinalis} , which is naturalized in the United 

 States (Fig. 294), Gypsophila Struthium of Spain and other 

 species of this genus, as well as species of Lychnis and Her- 

 niaria. The leaves of Paronychia argentea are used in Morocco 

 as a substitute for tea. The roots of Scleranthus peren- 

 nis of Eastern Europe are inhabited by an insect (Coccus 

 polonica} which is used in the preparation of a red dye. The 

 fleshy stitch-wort (Alsine crassifolia) of Europe and the United 

 States is poisonous to horses. 



XII. ORDER RANALES. 



The plants are mostly herbs, but include some shrubs and trees, 

 and comprise eight families of economic importance. 



a. NYMPH^ACE^: OR WATER LILY FAMILY. 

 These are aquatic perennial herbs with thick root-stocks and 

 floating, peltate leaves. The flowers are perfect and have large 

 petals. The seeds are enclosed in an aril, and the embryo has rieshy 

 cotyledons. 



Nuphar luteum of Europe and Middle Asia contains the alka- 

 loid nupharine and tannin, the latter of which splits into ellagic 

 and gallic acids. The yellow pond lily (Nymphcea advena) of the 



