382 PLANTS AND MAN 



Drugs Obtained from the Lower Plants 



All of the plant drugs mentioned above have their origin in 

 the highest plant group, the seed plants. Of the three plant drugs 

 discussed below, two, ergot and kelp, come from thallus plants; 

 the other, male fern, comes from a member of the fern phylum. 



Rye and other members of the grass family are attacked by a 

 fungus disease known as ergot, which results in a malformation 

 of the grain, and destruction of the food materials stored therein. 

 When ergot is eaten with rye it causes a form of poisoning known 

 as ergotism, which may be fatal to man or his domestic animals; 

 but ergot as a medicine has been responsible for the saving of 

 many human lives, since it increases the blood pressure and is 

 used for checking hemorrhages — especially in childbirth cases. 

 Ergot for medicinal purposes is generally produced in Northern 

 Europe, where cheap labor is plentiful for hand-picking the 

 infected grains. 



Certain brown seaweeds, especially the large forms known as 

 KELPS, which occur abundantly in the Pacific Ocean off the 

 coasts of the United States and Japan, are used in medical 

 practice as a source of certain mineral salts and vitamins which 

 are essential to the well being of the human body. Since sea 

 water contains, in addition to common salt, several of these salts 

 such as those of potash and iodine, the plant bodies of the kelps 

 are likewise high in their content of these substances. 



The MALE FERN, ouc of a group sometimes known as shield 

 ferns, ranges across northern North America and in Europe and 

 Asia. Its underground stems contain a substance long used in 

 medicine as a worm expellent. When taken into the alimentary 

 tract, this drug causes any intestinal worms, such as tapeworms 

 and roundworms, to relax their hold on the walls of the intestines, 

 after which they are purged from the body by the action of a 

 powerful cathartic. 



