ENTOMOLOGY 287 



tation by the coffee leaf- miner [Leucoptera coffeella Guer.) through 

 the destruction of its parasites. Bait-sprays have given variable 

 results, a reason suggested is that they destroy the parasites of 

 Antestia (Le Pelley 1933). There is also a considerable risk of 

 scorching the foliage, but in Tanganyika it has been found that this 

 can be avoided by using triple-strength arsenic bait-spray through 

 an improved fog-sprayer. 



The coffee capsid {Lygus simonyi Reut.), another bug distributed 

 throughout the coffee-growing areas of East Africa, injures the 

 flowers so that the fruit does not set. It is satisfactorily controlled 

 by pyrethrum-kerosene sprays in various forms. These sprays, 

 however, probably interfere with Coccinellid beetles controlling 

 Pseudococcus kenyae Le Pelley, a mealy bug which is not susceptible 

 to the spray and which was formerly recorded under the name 

 Pseudococcus lilacinus Ckll. P. kenyae is probably the most important 

 of a number of destructive mealy bugs, the identity of which is still 

 doubtful. In Kenya banding trees with kresotow and castor oil 

 against the ants which foster mealy bugs has been found successful 

 (James 1932). Mealy bugs are almost universally distributed in 

 coffee-growing districts. 



Another widely distributed major pest is the coffee berry-borer 

 {Stephanoderes hampei Ferr.). In Uganda and the Belgian Congo 

 a considerable measure of control is exercised by parasites, of which 

 the most effective is the Bethylid, Prorops nasuta Wtstn. Heterospila 

 coffeicola Schmied. is also of some importance (Sladden 1934). 

 Attention has been paid to the disinfestation of coffee beans: in 

 Kenya it has been found that exposing infested beans to heat rids 

 them of the borer, while in the Belgian Congo experiments have 

 been made on the fumigation of seed intended for planting. Tur- 

 pentine has been found to be a successful fumigant (Sladden 

 1932). In Nyasaland other pests, Anthores leuconotus Pasc. and 

 Thrips are of importance. 



In addition to the work on specific coffee pests, the fundamental 

 researches of Kirkpatrick (1935) ^t Amani are most important. 

 This work, which is mentioned in Chapter IV, is breaking new 

 ground in demonstrating the dependence of pests on the micro- 

 climates of their environment. 



