FISHES OF WESTERN SOUTH AMERICA PLATE I 
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PLATE I 
PoIsONING THE Rio CHANCHOMAYO FoR FisH, Usrtne THE Root or CuBr 
This small channel of the river has been partially cut off by a rough rock-and-branch dam to 
reduce the flow, then the root is bruised between rocks, and the alkaloid sap washed out into the 
water, giving it the milky appearance seen in the photograph. 
