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SOME EAST AFRICAN INSECTS OF 

 ECONOMIC IMPORTANCE. 



By R. H. DEAKIN, M.Sc, 



Lately Assistant Entomologist, British East Africa. 



The economic entomologist in East Africa has many duties to attend 

 to, and the time he devotes to research on insect life-histories (his 

 real object) is often very interrupted. The following notes, being 

 some of the results of intermittent research, during one-and-a-half years 

 residence in the E. A. P., without arriving at any important conclusions, 

 do at least, I think, throw some new light on the problems concerned. 



Locusts. Little attention in the past has been paid to locusts 

 as it is only at long intervals that they have caused damage. Natives 

 of various tribes speak of bygone years when locusts were very 

 destructive, but native memory for dates is rather uncertain. During 

 the first five months of 1914 unusual swarms of the adult locust, 

 Schistocerca peregrina, and in places, hoppers, appeared throughout the 

 Protectorate, not only in the areas of low rainfall of the N. and S.E. 

 but in the better watered regions around Nairobi, Naivasha, Nakura, 

 the Uasin Gishu and also near Lake Victoria. The damage done was 

 small, only the eating of the tops of a few coffee bushes and some 

 mealies, etc., being recorded: there appeared to be everywhere a 

 sufficient natural supply of food. I was unable, during a journey which 

 I undertook for the purpose, to obtain evidence showing that these 

 locusts had oviposited in any of the areas mentioned. I concluded 

 that they must have proceeded to more arid steppe-like regions for 

 this purpose. Rainfall statistics threw no light on a belief which I 

 entertained that this was an exceptional year of drought in the home 

 of the locusts— wherever this may be. Some facts relating to the 

 life-history of this locust have been worked out in German East Africa, 

 but the questions "When will they come?" and "Why <l>> they mine?" 

 are yet to be definitely ascertained. Nor is this a question of secondary 



Ann. Biol. U 16 



