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ELEMENTARY STUDIES IN INSECT LIFE 



and fully dormant. For scale insects, sufficient should 

 be applied to moisten bark of the tree. It is not safe to 

 apply in excess, since there is a liability of injuring 

 the tree. This substance should never be used during 

 the growing season. 



Fio. 232. " Kerowater " spray-pump. Designed for mechanically mixing and 

 spraying kerosene and water. The oil and water are mixed and discharged in 

 a milk-like emulsion. 



Inaccessible Insects. Carbon bisulphide, a very vola- 

 tile and highly inflammable liquid. The vapor is very 

 destructive to animal life. The vapor, being heavier 

 than air, is effective against root insects and insects 



