Remedial Afeasnres and Insecticides. xiii 



SUPPLEMENTARY CHAPTER. 

 Remedial Measures and Insecticides. 



In the following pages I have endeavoured to bring together 

 scattered information on the various methods that have been 

 employed in dealing with insect pests of the family Coccidce. 

 Though such treatment may in many cases be found suitable 

 to insect pests of other families, I do not propose to give here 

 a general treatise on insecticides, but to confine myself to 

 measures applicable to the subject of the present work. 



Little or no originality can be claimed for the following 

 remarks. They are very largely compiled from the published 

 work of trained entomologists (chiefly American) in different parts 

 of the world. America has long been in the forefront in the 

 practical application of economic entomology. 



Remedial measures may be discussed under two main headings : 

 Prevention and Cure. The former, being by far the more important, 

 will be dealt with first : — 



Preventive Measures. 



Of first importance amongst preventive measures, I would 

 place Quarantine Regulations. It is a fact, repeatedly demon- 

 strated, that imported pests are the most serious. An insect may 

 attract little or no attention in its original home, where it is kept 

 in check by its own natural enemies, a system recognised as ' the 

 Balance of Nature.' But take it away from its home ; place it 

 in a congenial climate with an ample supply of suitable food, and 

 it will multiply without the checks that have prevented its increase 

 in its original habitat. The very fact of extensive damage by any 

 insect may of itself almost be accepted as proof of its foreign 

 origin. Looking through the list of the different scale-insects 

 occurring in Ceylon, I find that all the more troublesome species 

 have been previously described from some other country, and are, 

 therefore, presumably imported insects. The home of the 

 ' Lantana bug' {Orthezia insignis) is now supposed to be some- 



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