HERBS, TUBERS AND BULBS. 335 



An indigenous species ( V. edulis), has large spindle-shaped roots, and is 

 said to have been used as food by the Indians. Centranthus ruber, or 

 Spurred valerian, has red flowers, and sometimes cultivated in European 

 gardens under the name of Jupiter's Beard. Readily increased by seed 

 or by dividing the roots. 



Verbenacece (Vervain Family). A small order of herbs and shrubs ; 

 the latter have already been noticed in previous chapters. See Calli- 

 carpa, Lantana, and Lippia, Of the true Verbenas there are a large 

 number of species, but those most usually cultivated in gardens are 

 descended from several South American species, but now so mixed that 

 it would be impossible to trace them back to the original types. New 

 varieties are raised from seed, and then propagated by layers or cuttings 

 of the young shoots. The latter mode is the preferable one, and for 

 stock plants to be preserved over winter, the cuttings should be struck 

 in August or September, and then kept in a rather cool house until 

 toward spring, when they are forced for the purpose of producing more 

 new shoots for cuttings. 



Violacece (Violet Family). This family is scarcely represented in 

 cultivation by any other genus than Viola, the true Violets and Pansies. 

 The most popular species is V. odorata, of which there are many varieties 

 in cultivation. Some are quite hardy, others tender and need slight 

 protection and are usually grown in cold frames where the temper- 

 ature may be under control of the gardener. There arc about thirty 

 North American species of Viola, but they are mostly scentless, or only 

 slightly fragrant. The Pansy or Heart's-ease, is deconded from V. tri- 

 color of Europe, and has been greatly improved, and the flowers 

 increased in size by cultivation. The Violets thrive best in a very rich, 

 light soil, and with a moderate temperature. Plants of easy culture 

 and all readily propagated by seed, cuttings, or dividing of the roots. 



