264 INTRODUCTION TO PLANT GEOGRAPHY [CHAP. 



anaesthetic ; digitalin, from the leaves of the European Foxglove, 

 almost indispensable in the treatment of heart ailments ; eucalyptus, 

 from various Blue Gum-trees of Australia but now widely cultivated 

 elsewhere, extensively used in medicine, for example in the treat- 

 ment of nose and throat disorders ; hamamelis, from the North 

 American Witch-hazel, used as an astringent ; henbane, from the 

 widespread weedy herb of that name, used as a sedative and hypnotic ; 

 stramonium, from the widespread and weedy Thorn-apple, used as 

 a narcotic and in the treatment of asthma ; and many others. 



From stems, etc., come ephedrine, from Asiatic Ephedras, used 

 in medical treatment e.g. of colds and hay-fever ; guaiacum, used 

 as a stimulant and laxative ; and quassia, used as a tonic and in 

 the treatment of malaria. From barks are obtained cascara, from 

 the American Western Buckthorn, used as a tonic and laxative ; 

 curare, from a variety of South American plants, a very powerful 

 poison used also in medicine and surgery ; slippery elm, made from 

 the familiar North American tree, useful for its soothing effect ; 

 and, above all, quinine, the great anti-malarial drug, obtained from 

 several allied trees native to South America and now cultivated 

 especially in southern Asia. 



From roots and other underground parts come an important series 

 of drugs including aconite, from the Eurasian Monkshood, used 

 particularly to relieve pain ; colchicum, from the Meadow Saffron, 

 whose active principle is colchicine, used in the treatment of 

 rheumatism and gout and also important in the plant sciences as it 

 produces doubling of chromosomes ; goldenseal, from the North 

 American plant of that name, used as a tonic and in the treatment 

 of catarrh ; ipecac, from forest-floor plants of tropical America, 

 almost indispensable in the treatment of amoebic dysentery and 

 pyorrhoea ; liquorice, from the Liquorice plant now much cultivated 

 in Eurasia, used as a flavouring, etc. ; squills and senega, used as 

 expectorants and stimulants ; ginseng, considered a virtual cure-all 

 in the Orient ; and valerian, from Garden Valerian, used to relieve 

 nervous afflictions. 



From various parts particularly of the Camphor Tree come 

 camphor and safrole, which have a wide variety of industrial and 

 medicinal uses. Among Pteridophytes, the tiny spores of some 

 Club-mosses are variously used for covering pills as well as in 

 industry and even warfare, while aspidium, obtained from certain 

 Ferns of the north-temperate regions, has long been employed to 

 expel Tapeworms. 



