30 



ASSOCIATION OF ECONOMIC ENTOMOLOGISTS. 



Rex solution, whitewash, K-L mixture, kerosene-whitewash, and 

 caustic soda. The number of eggs per tree was variable, but there 

 were not less than 400 eggs on each tree, and the maximum number 

 on one tree was 4,800. The total number of eggs by actual count 

 in the experiment was 223,920, of which 158,885 were firm, while the 

 rest were more or less shrunken. The trees were planted in boxes 

 of convenient size, and during the treatment were isolated to prevent 

 the applications from reaching other stocks. Each tree was exam- 

 ined daily, and as each egg hatched the aphis was killed and a record 

 was made of the daily hatching of the eggs. 



The results of the last two tests, which are representative, are as 

 follows : 



Fourth experiment: Less than 1 per cent of the eggs hatched on 

 trees sprayed with the sulphur wash, crude oil, kerosene-whitewash, 

 and Rex solution. The percentages of eggs that hatched on the 

 trees receiving other sprays are as follows : 



Per cent. 



Caustic soda 7. 3 



Kil-o-Scale 26. 



Checks 22.4 





Per cent. 



Scalecide 



8.9 



Kerosene 



0.7 



Kerosene emulsion 



7.0 



Whale-oil soap 



7.8 



Fifth experiment : Xo eggs hatched on the trees that received 

 applications of kerosene-whitewash and whitewash. On the trees 

 treated with the other sprays the following percentages of eggs 

 hatched : 



Per cent. 



Sulphur washes 3.5 



Scalecide 40 



Kerosene 1.5 



Kerosene emulsion G 



Whale-oil soap 



Per cent. 



Caustic soda 5 



Kil-o-Scale 4 



Crude oil 10 



Rex solution 1 



Cheeks 31.4 



Mr. Titus mentioned the fact that aphis eggs are often deposited 

 in such a manner on the twigs that they overlap, and this being the 

 case it would be difficult, and in some cases impossible, to cover all 

 the eggs with the spray material. In making an accurate statement 

 as to the percentage of eggs destroyed by spraying, this point and 

 parasitism should be considered. 



Mr. Hodgkiss replied that the small size of the trees enabled a most 

 thorough application to be made in each and every case. The pur- 

 pose of the experiment being entirely to test the advisability of spray- 

 ing nursery stock, the question raised by Mr. Titus w T ould in no way 

 affect the results obtained. Replying to a question on the value of 



