266 



JOURNAL OF ECONOMIC ENTOMOLOGY 



NICOTINE 



[Vol. 5 



Insects untreated were as lively as ever. 



The final results noted five days later are as follows: 



RESULTS EXPRESSED IN PERCENTAGE 



As seen from the above the different products vary but little in 

 their final results, although No. IV, a thick heavy preparation con- 

 taining a large percentage of the tobacco extract, shows more dead at 

 the first observation and a slightly higher percentage of killed insects 

 at the termination of the experiment. This difference, however, is 

 not great enough to recommend such a product over others having 

 the same percentage of nicotine. Pure nicotine (No. V) appears to 



