374 



PLANTS AND MAN 



in certain classes of the human race. The plant is now cultivated 

 for its seed in France and Spain. 



The HOP PLANT, native to the north temperate regions of 

 both hemispheres has been known since the time of the Roman 

 Empire, and has been cultivated in parts of Europe since the 

 ninth century. Hops are perennial climbing herbaceous plants 

 with male and female flowers borne on separate plants (fig. 241). 

 The female flowers contain several bitter, narcotic substances, 

 of which the most important is lupulin. When cultivated, as is 

 done in the United States, England, and Germany, the plants 

 are grown on poles and the hops are picked and dried in the 

 early fall. Their principal use is in the manufacture of beer, to 

 which they are added for their bitter flavor and to prevent 

 bacterial decomposition. They are used in medicine for their 

 soothing, sleep-producing efi'ects; also as a digestive tonic, and 

 sometimes in the form of a poultice. 



The dried flowers of chamomile, a daisy-like plant native to 

 Eurasia but widely cultivated, contain a volatile or essential oil 

 which is useful in overcoming stomach disorders, and as a tonic. 



The flower heads are dried and ground, 

 or broken up, and used to prepare an 

 infusion, or "tea" as it is often called. 

 Chamomile tea formerly was a staple 

 home remedy to relieve colic in young 

 babies. 



Drugs Obtained from Plant Leaves 



The drug cocaine is derived from 



the leaves of certain tropical shrubs 



cultivated since prehistoric times in Peru 



and Bolivia (fig. 242). The leaves have 



long been chewed by South American 



Indians, and its use enables the user to 



resist hunger and fatigue for long periods 



of time although habitual use leads 



to physical and mental breakdown and even death. The plant 



is widely cultivated in South America, Java, India, and Formosa. 



Coca leaves mature in three or four years, and crops are then 



Fig. 2 4 2.— Cocaine 

 comes from the leaves of 

 a South American shrub. 



