ENTOMOLOGY 293 



of serious loss to cocoa in the Gold Coast, but is fortunately incap- 

 able of withstanding the English climate. In Nigeria Ephestia 

 appears to be a dangerous pest to cocoa only when the crop is 

 kept in store for long periods, as in the financial depression of 193 1. 

 Research on the best methods of control is progressing there also. 



The same moth attacks other stored products as well, notably 

 tobacco and groundnuts. In the case of tobacco, the bumper crops 

 of 1928 and 1929 in Rhodesia led to an overloading of the market 

 so that large quantities were stored in British warehouses for un- 

 usually long periods. Great losses due to Ephestia and other insects 

 led to agitation from city brokers which did much to stimulate 

 research on its control. More recently attention has been drawn to 

 this moth in other parts of Africa, owing to severe losses of ground- 

 nuts. From 1929 to 1933 exhaustive research was carried out in 

 Professor Munro's department, and the reports by Munro and 

 Thomson (1929) and Bovingdon (1933) show that the insect is 

 particularly susceptible to humidity, so that control of warehouses 

 may prove comparatively simple. Various large manufacturers of 

 confectionery, notably Messrs. Cadbury, who obtain a large pro- 

 portion of their cocoa from the Gold Coast, are now assisting in 

 work on the control of humidity. The fumigation of warehouses 

 with hydrocyanic and other gases is also a satisfactory means of 

 control, but there is prejudice against it in the cocoa industry. It 

 has been widely used for the control of other storage pests, how- 

 ever, and a fumigation apparatus is now established in Kenya for 

 experiments in grain warehouses. 



Attacks by Ephestia on groundnuts in store have been most pro- 

 nounced in Senegal. Preventive methods have been the subject 

 of study by Sagot and Bouffil (1935), working at the agricultural 

 station of M'Bambey. They conclude that the pest can be con- 

 trolled only by insecticides, of which Datura, which materially 

 checks the multiplication of the insects without damaging the nuts, 

 is most to be recommended. 



In Southern Rhodesia Ephestia is only known on a few tobacco 

 premises, but the beetle Lasiodernia serricorne F. is generally dis- 

 tributed and causes heavy losses. Both these pests are the subject 

 of a report by Mossop (1932b). Hygienic conditions on premises 

 used for handling and storing tobacco are enforced by legislation 



