103 



COCOA-NUTS. 

 SCALE INSECTS AND WHITE FLY. Hemiptera. 



Cocoa-nuts are attacked by scale insects, which are to 

 be found most abundantly on the older leaves. The most 

 important of these is probably the Bourbon Aspidiotus 

 (Aspidiotus destructor, Sign.) This is a small insect, the 

 scale covering of which is thin and papery, with a pale 

 yellow central spot (Fig. 110). Enormous numbers of this 



Fig. 116. Bourbon aspidiotus. 

 Enlarged. (Imperial Dept. Agric.) 



insect are often found very closely crowded together ; 

 badly attacked leaves often have a yellowish or dried-up 

 appearance. 



This scale insect is attacked to some extent by lady- 

 birds, and is probably parasitized by hymenopterous 

 parasitic insects ; but the extent to which this occurs and 

 the species which are concerned in it do not seem to be 

 recorded. In Cuba, the Bourbon Aspidiotus on cocoa-nuts 

 is effectively controlled by the spotted lady-bird (Chilocor- 

 us cacti). 



The cocoa-nut snow scale (Diaspis boisduvalii, Sign.) 

 Fig. 117 also occurs on the leaves, causing yellowish 

 spots. The colonies are generally small ; the female scale 

 is pear-shaped, and similar in colour to the leaf, while the 



