320 POPULAK ECONOMIC BOTANY. 



the name of Pulvis Comitissce, or Countess's Powder ; its 

 value was made known to the natives of Europe chiefly by 

 the agency of the Jesuits, whence it also received the name 

 of Jesuits' Bark. 



The value of the Cinchona barks is now known to de- 

 pend entirely upon the presence of two peculiar chemical 

 principles, called Quinine and Cinchonine, which are ex- 

 tremely effective in febrile diseases, especially those which 

 are intermittent. 



The Cinchonas are trees of moderate size, often not more 

 than twenty feet, and rarely exceeding twice that height ; 

 they bear a profusion of small white or roseate tubular 

 flowers, and have handsome shining lanceolate leaves 

 placed oppositely on short petioles. The species which are 

 valuable for their bark are numerous, the following are 

 however the principal ones : — 



C. Condaminea, yielding Crown or Loxa Bark. 



C. micrantha, „ Huanuco, Grey, or Silver Bark. 



C. ovata, 

 C. purpurea, 

 C. (species ?) 

 C. (species?) 



Ash Cinchona. 

 Rusty or Huamalies Bark. 

 Calisaya, or Eoyal Yellow Bark. 

 Red Bark. 



These barks are usually in the form of quills, some sorts 



i 



