52 COCONUT PLANTER'S MANUAL. 



same plot of land. The young locusts when in the wingless stage 

 usually cluster together in large masses on the ground or on low 

 branches and can be beaten down or collected into sacks and crushed 

 or submerged in water, 



In addition to the Coconut caterpillar {Nephcmtis serinopa) there 

 are at least three other caterpillars which are occasionally found in 

 small numbers eating the green leaves of coconut palms. 



The " Bagworm " {Psyche alhipes) covers itself with a case formed 

 of small pieces of leaf and eats irregular holes in the leaflets, or some- 

 times eats away portions of the leaflets until only the midrib remains. 

 The cases should be collected and destroyed. 



The " Blue-striped Nettle-grub " (Parasa lepida) sometimes feeds 

 on the leaflets, at first nibbling away small portions of the leaf surface 

 mid later eating right through the leaf. The egg-shaped cocoons arc 

 sometimes seen attached to the leaves. 



The Hesperid caterpillar-, Gcmga/ra thyrsis, occasionally attacks 

 the leaves, but cannot be considered a pest. 



Scale Insects. — There are several species of scale insects which are 

 found on the leaves of coconut palms, but the only species which calls 

 for any mention here is the " Coconut Scale," sometimes known as the 

 " Transparent Coconut Scale" (Aspidiotus destructor). This scale is 

 not the serious pest in Ceylon that it is in some other countries, as it 

 seems to be controlled by parasites and by fungous diseases. The 

 female scale is pale yellow and is usually seen as a minute yellowish 

 spot under a thin papery covering. These scales are sometimes clus- 

 tered so thickly on the underside of the leaves as to form a complete 

 scurfy layer ovei the leaf surface. The upper surface of attacked 

 leaves is usually marked with small yellowish spots which coalesce in 

 a bad attack, giving the whole leaf a yellowish appearance, but this 

 yellowing of the leaves may also be due to other causes. Small palms 

 are sometimes attacked on the lower leaves, which can either be 

 sprayed with kerosene emulsion, or removed and burnt. Attention 

 to drainage, cultivation and manuring will maintain the vigour of 

 the palms and help to keep down scale attack. 



See also : — Bulletin of the Department of Agriculture, No. 5§ and 

 leaflets Nos. 20, 21, and 22, 



