256 COCOA 



normally until, sometimes very suddenly, a black spot 

 appears, often when the fruit is almost ripe (Fig. 84, C). 

 When such a fruit is broken, it is found that the tissue 

 of the fruit wall at the spot is exceptionally hard 

 ("hardening" or "induration" of pods), while the 

 seeds are mostly brown and spoiled. 



The fungus is able to penetrate into the fruit-cushions 

 by means of the stalk of the hardened pod. When the 

 fruit-cushion buds, the result is the production of a great 

 number of crowded blossoms which produce worthless 

 fruits, or none at all. 



By microscopical investigation the fungus is seen 



FIG. 85. Fructifi cation of the Surinam witch-broom fungus. 



running between the cells of the attacked parts, and its 

 characteristic mycelium is especially abundant in the 

 hypertrophied tissues. It fructifies (Fig. 85) with 

 whitish or slightly reddish fruiting bodies, which appear 

 sometimes at the base of the hypertrophied twigs, but 

 much more freely on decaying hardened pods. These 

 form, therefore, a much more dangerous source of infec- 

 tion than the " witch -brooms." 



The disease has never been found on any other 

 cultivated plant, but the wild - growing Theobroma 

 speciosum has been observed to be very liable to it. 

 This plant grows wild in the south of Surinam, and in 

 Brazil in the basin of the Amazon. As in Surinam 

 the disease was probably transferred from this wild 

 Theobroma speciosum to the cultivated Theobroma 



