CERTAIN POISONOUS PLANTS 



The cactus is indigenous to the arid regions border- 

 ing on the lower Rio Grande both in the United 

 States and Mexico. It 

 resembles a carrot in 

 shape, and the entire 

 plant, except about an 

 inch at the top, grows 

 underground. This top 

 is flat and round, two to 

 three inches across, and 

 wrinkled with radiating 

 ribs. There are no 

 spines but numerous 

 tufts of silky hairs, amid 

 which pink blossoms are 

 borne in season. The 

 chemical properties em- 

 brace three alkaloids 

 whose effect is power- 

 fully narcotic and delir- 

 iant, in some respects re- 

 sembling opium. Lum- 

 holtz, in his "Unknown 

 Mexico," gives an inter- 



Mescal-button 

 (Lophophora WilliamsU) 



the Ancient Americans," in Ann. Kept. Smithsonian Institution, 

 1916. 



253 



