mCOTTLEDONES. 221 



a large tree in Guiaua aud Brazil. The bark of our native 

 Prickly Ash (Zanihoxylivm Americanum) is used medici- 

 nally. A few species are cultivated for ornament, as 

 Dictammus (Fig. 331), etc. 



i8. Geraniaceae. The Geranium family consists 

 mostly of herbs, seven hundred and fifty species, found in 

 the temperate and hot tropical regions, many of which are 

 ornamental. The Garden Balsam, or Touch-me-not (Jm- 

 patiens Balsamina of India), has been cultivated for nearly 

 three hundred years. Many exotic species (from South 

 Africa, etc.) of OxaUs are found in cultivation. The South 

 American genus Tropeeolum furnishes the Nasturtion (T. 

 magus) ; also edible tuberous roots (from T. tuberosum), used 

 instead of Potatoes in Peru. Most of our fine cultivated 

 " Geraniums" belong to the South African genus Pelargo- 

 nium. The Alfilaria of California (Erodimn cieutariurri) 

 is said to be a nutritious forage plant. 



19. Linaceae. The Flax family. Species one hun- 

 dred and thirty-five, widely distributed. Herbs, shrubs, 

 and a few trees, with single sessile leaves, and regular, 



Fig. 331. Pictamnixs, an ornameatal species. 



