INSECT PESTS 41 



the powder falls on to the plants, and two rows can 

 thus be dusted simultaneously. 



The Egyptian cotton worm (Prodenia litura) does 

 much harm to " berseem " (Egyptian clover) and 

 cotton in many districts. The moth lays its eggs on 

 the under-surface of the leaf in batches of two or three 

 hundred. This behaviour is quite different from that 

 of the American cotton worm which lays its eggs on 

 nearly every leaf of the plant and seldom more than 

 three or four on the same leaf . The chrysalis is found 

 in the soil instead of within the folds of a leaf as in the 

 case of the American insect. The following methods 

 are recommended for the prevention of damage by 

 this pest. The soil should be prepared as long as 

 possible before the cotton is sown. The plants should 

 be examined every few days, and all leaves on which 

 eggs have been deposited should be collected and 

 burned. Difficulty was experienced in the past in 

 Egypt in obtaining a sufficient supply of labour for 

 this work, and the Government therefore issued a 

 decree making compulsory the collection and destruc- 

 tion of infested leaves and insisting on the employ- 

 ment of children to do the work at definite periods. 

 This now forms one of the ordinary field operations, 

 and the pest has been much reduced by a law pro- 

 hibiting the watering after April of berseem, in which 

 the cotton worm lives. 



The Indian cotton leaf-roller (Sylepta derogatd) 

 sometimes causes serious damage. The pest can 

 usually be checked by picking off the affected leaves 

 and burning them, but in serious cases it may be 

 necessary to spray the plants with lead arsenate. 

 This moth has also been observed attacking cotton 

 plants in Southern Nigeria and East Africa. 



Cutworms. The larvae of certain moths, especially 

 species of Feltia and A gratis, eat off the plants just 

 as they come up. They feed at night, and the best 

 method of combating them is to place arsenicated 

 cabbage leaves or grass in places where they have 

 appeared. The larvae crowd under these for shelter 

 during the day and are thus destroyed. It has been 

 suggested in Egypt that the addition of small quan- 



