PROPERTIES OP COMPOSITE PLANTS. CAMPANULACEJE. 



465 



species of which any part is eaten being a kind of Sun-flower, 

 of which the root is known under the name of the Jerusalem 

 Artichoke. The former part of the name is a corruption of the 

 Italian Girasole, which means " turning towards the sun." The 

 seeds of the common Sun-flower are a nutritious food for poultry, 

 and they are made into cakes by the North American Indians; a 

 large quantity of a fixed oil may be extracted from them (. 371). 

 The roots of the Dahlia are fleshy, but their taste is very dis- 

 agreeable. Of the medicinal properties of this group, those of 

 the common Chamomile, which is in repute as a tonic and 

 stomachic, are a good illustration ; but there are many species in 

 which the bitter, the resinous, or the astringent properties are 

 more predominant, and which have, therefore, their respectively 

 peculiar uses. 



637. Quitting this extensive and important order, we next 

 proceed to one which appears very different, but which has, never- 

 theless several points of affinity with it ; this is the order CAM- 

 PANULACE^:, or Hairbell tribe, an extensive group, of which the 

 species are scattered all over Europe, and in the cooler parts* of 

 Asia and America, dwelling in dells and dingles, by the banks 

 of rivers, in shady groves, and on the sides of mountains. The 

 British species are humble plants, bedecked with no other orna- 

 ment than a few blue or purple nodding flowers ; but in many 

 foreign countries there are species of great brilliancy and rich- 

 ness of appearance, which 



are more striking from 



the barren nature of 



the situations in which 



they usually grow. The 



genus Campanula is so 



named from the bell-\\ke 



form of its corolla ; to 



which the latter part 



of its common English 



name Hairbell also 



refers. Of this genus alone there are eight species in Britain, 



any one of which may be selected for examination. The calyx 



FIG. 170. DIAGRAM OF THE FLOWER OF CAMPA- 

 NULACEJE. 



