346 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 14 



tion of 1 to 100 with a 95% mortality resulting. On March 12th the 

 material at a dilution of 1 to 300 was sprayed and counts showed 650 

 dead aphids on the sprayed twigs, representing 100% mortality. The 

 check selected, having 200 aphids on it, showed only 9 dead at the time 

 the counts were made on the sprayed bushes. 



The bean aphis on nasturtium was sprayed Oct. 5th with a dilution 

 of 1 to 100 resulting in 100% mortality. 



On Oct. 6th potted chrysanthemiims badly infested with the brown 

 aphis were sprayed with dilutions of 1-100, 1-300 and 1-500 prepared 

 just prior to spraying and 1-300 that had been diluted five days. Exam- 

 ination Oct. 7th showed one live wingless aphid on the plant sprayed 

 with a dilution of 1 to 300, (freshly prepared), and one live winged aphid 

 on the plants sprayed with 1 to 300 (prepared five days). On Oct. 13th 

 three chrysanthemum plants badly infested with brown aphis were 

 sprayed with 1-1000, 1-1500 and 1-2000. Notes made Oct. 14th and 

 16th disclosed almost complete control. These tests were repeated 

 Nov. 10th on mtrais in bloom using 1-SOO and 1-1000 that had been 

 made up one week from a new lot of the insecticide and 1-2000 that 

 had been made up on Oct. 14th from the original sample. The former 

 application did not control the aphids while the 1-2000 gave complete 

 control. Later it was learned that the second sample was only one- 

 half the strength of the first sample so that for comparative purposes 

 the above solutions would represent dilutions of 1-1600 and 1-2000. 

 Just what factor caused the decided difference, cannot be stated. On 

 May 15th, 1920, Japanese barberry bushes heavily infested with aphids 

 were sprayed at the rate of 1-600. Nearly complete control was ob- 

 tained in this case. 



A very insufficient test of the effect on the eggs of the imported cab 

 bage worm is herewith given for what it is worth. Three lots were 

 sprayed respectively with strengths of 1-100, 1-300 and 1-500. Two 

 lots of two eggs each were retained as checks. One egg in each lot of 

 checks hatched on the 11th of October while none of the sprayed eggs 

 hatched. Mealy bugs on coleus were sprayed with a dilution of 1-100 

 October 1st with no perceptible beneficial rerults. On the red spider 

 the results were likewise unsatisfactory. 



Field te-^^ts on full grown tent caterpillars at a dilution of 1-600 gave" 

 100% control. Laboratory tests at various dilutions from 1-100 to 

 1-600 gave complete control in all cases, though the time necessary to 

 kill depended upon the strength of the solution and the size of the lar- 

 vae. 



Rose bushes thoroughly infested with the Bristly Rose Slug in the 

 green-house were sprayed with a dilution of 1-100. All slugs were 



