60 The Tea, insects of India. 



Kerosine Emulsion. 



This insecticide is said to be very widely used in the United States 

 against Aphidse, scale insects and other soft-bodied insects, which 

 feed by sucking up the juices of plants bj means of a proboscis inserted 

 in the tissues of the plant, and which are hence little affected by non- 

 volatile poisons distributed on the surface of the leaves. In particular 

 it is said to have proved very valuable in Florida for ridding orange trees 

 of scale insects. 



In India it has been favourably reported upon for destroying the 

 green scale bug, which is one of the most inveterate blights of the coffee 

 tree, also for dislodging white ants. It is further said to have been 

 successfully used in the Kangra Valley for destroying scale insects on 

 tea, and has been recommended by Mr. Green to the attention of Ceylon 

 tea planters for dealing with the five-ribbed tea mite {Typhlodromus 

 carinatiis, Green), the tea Aphid [Cey Ionia ihececoala^ Buckton), and such 

 scale insects as Ckionaspis thecBy Maskell. It is further worthy of very 

 much more careful trial than has yet been accorded it against such 

 insects as mosquito blight and green fly blight. For although it may 

 be impossible, without seriously injuring the foliage, to make it suffi- 

 ciently strong to destroy the winged adult forms of these species, which 

 fly off as soon as spraying commences, it by no means follows that it will 

 be ineffectual against the wingless larvse which also subsist upon the 

 tea bush, where they not only do a considerable amount of injury them- 

 selves, but also eventually develop into the winged form. No doubt 

 the best thing would be an insecticide capable of destroying, on the first 

 application, alike the eggs, the larvse and the adult insects, without 

 injury to the tea bush, but tailing this it is quite possible that useful 

 results may accrue by the persistent use of less powerful agents, provided 

 they are really effectual against any one of the forms through which 

 each individual insect passes the course of its existence. For, to take 

 a single instance, it is obvious that there cail be no winged mosquito 

 blight to lay eggs, if all the wingless larvse have been destroyed as fast 

 as they appeared. 



Kerosine emulsion is made by violently churning two parts of kero* 

 sine oil, the purer the better, with one part either of milk or, better, of 

 soap solution ; the soap solution to be made by boiling from a quarter 

 of a pound to a pound avoirdupois of common yellow soap or whale oil 

 soap with a gallon of water. The resulting emulsion is then mixed 

 with from nine to fifty parts of water. The churning is beet done 

 when the mixture is warm and should be continued until a thick cream 

 like emulsion is produced, almost like butter in consistency. In the 



