2S4 Wisconsin State Horticultural Society. 



The same experiments as those detailed above were tried with 

 the potato beetle {Doryphora ten lineala). Those in the boxes 

 were all down in fifteen minutes, both beetles and larvae ; nor did 

 they recover. I watched those on the vines for twenty minutes, 

 when several had fallen to the ground. These'were some distance 

 from my home, and I could not watch them longer. "Whether all 

 dropped or not I am not able to say, nor whether all or any re- 

 covered. 



Wednesday, September 29, 1880. 



In the following experiments, the cabbages were simply dusted 

 or sprinkled, with no effort to secure actual contact of the liquid 

 or powder with the larvae. The experiments were tried under 

 my direction by a very trusty and careful assistant, with the fol- 

 lowing results : 



First experiment — By use of a common sprinkler, nine cab- 

 bages were treated with the liquid mixture, composed of one 

 tablespoonful of Pyrethrum (seven grammes) to a gallon of water. 

 In one and a half hours after the application, a hasty examina- 

 tion discovered thirteen dead larvae and three live ones. 



Second experiment — Ten cabbages were treated the same as 

 above, except that two applications of the liquid were made ; 

 nineteen dead larvae and one live one were found. 



Third experiment — Twenty-six cabbages were treated with a 

 liquid mixture of one tablespoonful of the powder to two gallons 

 of water. One application was made with Whitman's fountain 

 pump. Eleven dead and four live larvae were found. 



Fourth experiment — The same as experiment three, on thirteen 

 cabbages, except that two applications of the liquid were made. 

 There were five dead caterpillars and two alive. 



Fifth experiment — Twenty cabbages were dusted with a 

 powder compound of one part of Pyrethrum to forty of flour. 

 Five dead larvae and one live one were found. 



Sixth experiment — Twenty cabbages were treated the same as 

 number five, except that the mixture was in the proportion of 

 one to twenty. Three dead and three live caterpillars were found. 



The examinations in all the above cases were made one and a 

 half houis after the application of the liquid. The examination 

 was too hasty to be thorough. 



