COCOA-GROWING COUNTRIES 327 



ably they have been spread from the roga " Monte 

 Cafe," which imported them in 1882 in Wardian cases. 



Enemies and diseases. - - The principal animal 

 enemies of the cocoa are the rats, which cause a great 

 deal of damage. De Alrnade Negreiros estimates it at 

 one-fifth of the crop. They feed on the pulp which 

 surrounds the seeds and then drop the seeds ; these are 

 collected, dried, and exported to Europe as the most 

 inferior quality (" Cacao dos rabos "). Besides, white 

 ants cause considerable damage. 



One borer has been studied by Granier ; it is the cater- 

 pillar of some Zeuzera, perhaps Zeuzera coffeae. The 

 caterpillar finds its way into the branches, bores a passage 

 which may be 12 mm. in diameter and 50 cm. long. 

 The attacked branches die ; the leaves get dry and 

 remain on the branches. 



The best way of fighting this insect is the cutting 

 and burning of the infected branches, so that the cater- 

 pillar and chrysalides are destroyed. 



There are other borers in the cocoa plantations, but 

 not in large numbers, arid the caterpillars principally 

 attack unhealthy trees. 



In the south of the island it sometimes occurs that 

 several trees die suddenly. In some cases it appeared 

 that the roots had not been able to penetrate into the 

 stony or clayey layer ; in others the roots had been 

 attacked by a fungus. The fructification of this fungus 

 has not yet been found. 



A pod disease occurs, which makes a sort of brown 

 rot : it generally begins with the fruit-wall ; the tissue 

 gets soft, and soon the infection spreads all over the pod. 

 Chevalier sent some pods to the " Laboratoire de 

 Cryptogamie du Museum " in Paris. They were examined 

 by Hariot and Patouillard, who on nearly all of them 

 found a Botryodiplodia. It is, however, probable that 

 this organism is not the cause and was preceded by 

 Phytophthora. 



Export duty. An export duty is raised, amounting 

 to 5s. 8d. per 100 kilograms when the cocoa goes in 



