188 MEDICINAL AND POISONOI^S PLANTS 



from the hark of tlic ( 'alisaya-l rcc (M^. 17()) and i-clutcd 

 species. Its great and widely ret'ORnizi'd value in the tr(>at- 

 ment of iiiahiria is explained by the faet that in <|uantities 

 not seriously injurious to a human being the alkaloid acts 

 as a deadly poison upon minute i>arasites which occur in 









Fir.. 17(1. — Calisaya-troi- {(' iiicliniin Cnh'snyn, Madder Family. Ruhiamr). 

 .1, tlo\y(Tiiit!: hraiicli, .,'. li. llowrr. ('. ronilla and staniiais. D. fruit. 

 E, fruit with upper half of wall removed to show the paeking of the 

 seeds. F, fruit, cut across. G, seed, enlarged, and cut tlirough the 

 emhr.vo, lengthwise. (Luerssen.) — Tree aliout 12 m. tall; leaves pale 

 green; flowers iiink; fruit dr,\-. Native home, Andes of Peru. 



the blood of malarial patients and are regarded ;is the cause 

 of the disease. It is highly valued also as a tonic. Its in- 

 tensely bitter taste is a property fa,miliar to most ptM-.sons. 



Strychnine (C".;|IL.jN.,(K), the principal alkaloid obtained 

 from the ,se(>ds of the nux vomica tree (Fig. 177), is one of 



