SOCIETY OF CENTRAL ILLINOIS 



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first released ; but the effects of the poisons were nevertheless 

 evident, as shown by the subjoined table: 



Paris Green Experiment No. 1, April 19, 18S9. 



May 4, this experiment was repeated with a fresher lot of 

 beetles, with more marked results, curculios commencing to die 

 two days after treatment in all the poisoned lots but one, all of 

 one lot being dead in nine days, and in ten days, all of every 

 poisoned lot but a single beetle. In the check lot, meanwhile, 

 only one had died. 



In both the above experiments, as also in the following, peach 

 leaves were used as food, and these were sprayed but once. 



All strengths of the poison mixture here killed the beetles feed- 

 ing on it, the difference being seen in the rapidity with which 

 they took effect. In four days from poisoning, the ratios killed 

 were forty-two per cent, in lot two, thirty-three per cent, in lot 



