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masses, frequently abnormal, and many of the pedicles 

 give off branches which become vegetative in character 

 and take the form of small witches' brooms. This 

 entire structure dies quickly, the vitality and productive- 

 ness is reduced, and if the disease is severe the tree dies. 

 The fruits also suffer from this disease, which attacks 

 them when young, causing the diseased areas to become 

 hard and swollen, and eventually to blacken. The 

 diseased pods rarely mature, but fall when about half- 

 grown. 



This disease has been described by Eitz. Bos as due 

 to the fungus Exoascus theobromae, and later by Van 

 Hall and Drost as due to Colletotrichum luxificum. 

 It is also thought that this disease may have been 

 confused by planters with the Phytophthora faberi 

 Maub. However, all authorities agree that the only 

 practical method for the control of this disease is the 

 cutting and burning of these brooms as soon as observed, 

 and the painting of the wound with tar or some other 

 protective substance. 



Another witches' broom, which is said to be due to 

 Taphrina bussei, Yon Faber, attacks the young shoots 

 and leaves in Kamerun. 



Cankers. Among the most important diseases of the 

 cacao are the cankers which are usually caused by the 

 species of the genus Nectria. These cankers cause the 

 death of all parts of the plant beyond the point of 

 attack. 



Nectrias. Fungi belonging to the genus Nectria are 

 frequently mentioned as causing diseases on the branches, 

 fruits, and trunks of the cacao, and several species have 

 been described. However, in many cases the writer is 

 unable to determine from the semi-popular accounts 

 just which is referred to. The most injurious are those 

 which attack the stems and branches. They are very 

 widely distributed. 



Nectria cinnabarina, (Tode)Fr.,of Jamaica, 1 attacks 



1 This species is not mentioned by Stockdale, one of the recent writers on the 

 diseases of the cacao in the West Indies. 



