1917 ENTOMOLOGICAL SOCIETY. 53 



Black Leaf 40 was also tested as a repellent. This was used in the pro- 

 portion of one part to 686 parts of water, both with and without oil of citronella. 

 Fair repellent action was secured in the latter case, but this was evidenced for 

 such a very short time that tlic mixture could not be considered of any practical 

 value as a fly repellent. 



HOME-MADE REPELLENTS. 



L Kerosexk Emulsion: 

 V2 lb. yellow soap. 

 ■ 1 gal. soft water. V After preparation, add 1 gal. water. 



2 gals, kerosene. 



} 



This was used in piioportious of 1 to 5 and 1 to 3 of water, both with and with- 

 out oil of citronella. At no strcn.i^th used was repellent action secured, which was 

 sufficient to eiuible us to consider it of any value for practical use. 



IL Flour Emulsion: 

 6 oz. flour. 



1 qt. kerosene. 



2 gals, water. 



As with Kerosene Emulsion, the repellent action secured with this mixture 

 was so sliglit and of such short duration as to bo of no practical value. 



III. Milk Emulsion: 



Slightly sour milk, one part. 

 Kerosene, two parts. 



This stock solution was used iu proporti-an 1' 1 to 15, 1 to 12, and 1 to 8, of 

 water, both with and without oil of citronella. When used in the proportion of 

 1 to 8, with oil of citronella, very fair repellant action was secured, which was quite 

 plainly evident on the day following the spraying. This suggested to us that the 

 milk emulsion could be used as a medium for the application of some substance with 

 a stronger repellent action. The milk emulsion we found could not be used as a 

 practical repellent in itself, because of the large quantities which it was found 

 necessary to apply to each animal. 



IV. MiT.Tc- Emulsion and Olive Oil: 



1 part slightly sour milk. 

 1 part kerosene. 



1 part olive oil. 



This stock solution used 1 to 8 parts of water. The repellent action secured 

 was comparatively slight and in any case the inlroduction of olive oil made the 

 spray so costly that it could not be considered of practical value, even though much 

 smaller quantities could be used than was the case with milk emulsion itself. 



V. MiLTv E:\iULSioN AND LiNSEED Oil: 

 StocJf Sohdion No. 1. . " 



2 parts slightly sour milk. 



2 parts linseed oil. 



3 parts kerosene. 



Used in proportions of 1 to 8, 1 to 4, 1 to 2. both with and without oil of 

 citronella. Even in the proportion of 1 to 2 with the addition of oil of citronella, 

 the repellent action secured was only fair, and the cost was such -that the mixture 

 could not be considered of practical value. 



Stock Emulsion No. ,?. 



1 part slightly sour milk. 1____ _ 



1 part linseed oil. ' 



3 parts kerosene. 



