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of the very large scale on which trials of this interesting work 

 are being carried out in various parts of the world. In the 

 West Indies, there are several very good instances of the efficiency 

 of natural enemies in controlling insects which, without their 

 influence, would become pests of importance. 



The black scale of cotton has already been mentioned as 

 having been a serious pest in Barbados a few years ago. The 

 very complete control which was assumed over this pest by its 

 parasite, a small hymenopterous insect to which the name 

 Zalophothrix mirum Crawford," was given, resulted in almost 

 entirely freeing the cotton crop from attacks by this pest. That 

 is to say, the black scale was so quickly overcome by its parasite 

 on its appearance in the cotton fields in Barbados, that for 

 the past five or six years there has been practically no loss 

 occasioned by the attacks of this insect in this island. In other 

 cotton-growing islands, however, this parasite has not con- 

 trolled the black scale so completely as in Barbados, but its 

 influence has without doubt been very beneficial. 



For a number of years the question of black blight in Grenada 

 was considered to be very serious.^' Many trees, especially 

 mangoes and others, which were nearly always infested to a 

 certain extent by scale insects, were seen to be covered with 

 the black blight or sooty mould, a black fungus of the genus 

 Capnodium, which is nearly always found to be associated 

 with the occurrence of scale insects. 



About three years ago the study of the entomogenous fungi 

 in the West Indies was undertaken by Mr. South, who published 

 a paper on the Control of Scale Insects in the British West 

 Indies by means of fungoid parasites, in the West Indian Bulletin, 

 vol. xi, p. i.^' As a result of this study the agricultural officers 

 in Grenada began to devote their attention seriously to the 

 use, under control, of the shield-scale fungus {Cephalosporium 

 lecanii). Scale insect material bearing this fungus was dis- 

 tributed in different parts of the island where black blight 

 occurred abundantly, and it is now reported by the Agricultural 

 Superintendent that the decrease of scale insects and black 

 blight in Grenada has been very marked. In Dominica there 

 is a very considerable cultivation of citrus frvfits, especially limes, 

 and in that island several of the pests of these trees occur. It 



