280 IN THE GUIANA FOREST. 



then, we have evidence of reasoning power of a 

 very high order, unless we credit the grand 

 discovery to accident. The lower animals develop 

 the power of assimilating poisons without injury ; 

 man drives them off by cooking. 



One of the reviewers of the first edition calls 

 attention to the fact that some varieties are in- 

 nocuous. This is true to a certain extent, but even 

 these are not quite wholesome until cooked. It is, 

 however, the "bitter" cassava (the poisonous) 

 which is always used for bread. 



