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or at least thoroughlj' cleaned if found infested ; this last point is an 

 important one, as the insect has undoubtedly been introduced into 

 new districts through the agency of auction houses, and has often 

 become extremely abundant before being recognized as anew enemy. 



These precautionary measures should be supplemented by frequent 

 syringing with as severe a spray of water as the plants will stand if 

 any insects make their appearance. Many plants like coleus, how- 

 ever, will not stand a syringing severe enough to wash ott" all the 

 insects, and so resort to an insecticide is often found necessary. 



Of the florists who use an insecticide against this insect, nearly all 

 use fir-tree oil, and all who do speak very highly of its ettectiveness. 

 This substance has been tried at the Insectary, and when used in the 

 proportions recommended by its manufacturers for the Mealy Bug, 

 it has been found to be very efficient in destroying the Greenhouse 

 Orthezia. Its costliness is the greatest objection to its use. 



Kerosene emulsion is another good insecticide, and one that is not 

 as commonly used by florists as it deserves to be. Doubtless this is 

 because it is a little troublesome to prepare, but those who are willing" 

 to take this tr.>uble are well repaid. The emulsion which was found 

 to be the most efficient on the Greenhouse Orthezia in experiments 

 conducted at the Insectar}' was Cook's emulsion. This is made by 

 adding one pini, of kerosene to a boiling solution of one-quarter 

 pound of hard soap in two quarts of water, and churning the mixture 

 thus formed until it is thoroughly emulsified, which takes about five 

 minutes ; for use, the emulsion is diluted with twice its bulk of water. 

 It must not be expected that every insect will be destroyed by one 

 application of either fir-tree oil or kerosene emulsion, and besides, 

 the eggs in the ovi-sac are not always reachad. Dipping the plants 

 in the substance and holding them submerged for a few seconds 

 appears to be a more successful method than spraying them. 



The insects remaining on the plants left out of doors are killed by 

 the first severe frost, so no danger need be apprehended fri)m them. 



