160 WASHING AND SUN-DRYING COCOA 



these insects feed upon the cotyledons, and the integu- 

 ments of badly infested beans contain little else but 

 their excreta. Pyralid moths have been often observed 

 hovering over, and settling upon, cocoa beans which 

 have been spread out in the sun to dry. It is probable 

 that this moth lays its eggs in or upon the beans at 

 this period, and although the beans appear to be quite 

 sound when placed in the storehouse, they may be badly 

 attacked by larvae shortly afterwards. 



Storehouses which are infested with either Arccocerus 

 coffcce or Ephestia cautdla should be frequently cleaned 

 out and limewashed, and the cocoa stored in them should 

 be constantly examined. 



The larvse in the beans may be destroyed by pouring a 

 small quantity of carbon bisulphide upon cotton-wool, or 

 some similar absorptive material, and placing this in 

 each sack containing larvae-infected beans, and tightly 

 closing the sack. About a fifth of a drachm of the 

 liquid is usually sufficient to kill all the larvae in a sack 

 of cocoa. Owing to its inflammability it is inadvisable 

 to bring naked lights in the neighbourhood of the 

 vapour of carbon bisulphide. This substance has no 

 injurious effect upon cocoa, and its unpleasant odour 

 disappears when the beans are exposed to air. The vapour 

 of carbon bisulphide appears, however, to have no effect 

 on the eggs of the insects ; it is therefore sometimes 

 necessary to apply the substance on more than one 

 occasion, as, although the first application may destroy 

 all the larvae present in the beans, more may develop 

 from the unhatched eggs. 



