MERIA 461 



PELLICULARIA (Cooke) 



Parasitic. Hyphae creeping, branched, septate, interwoven 

 to form a sub-gelatinous film ; conidia sessile on the prostrate 

 hyphae, solitary, hyaline. 



Coffee leaf rot. This disease was first observed on coffee 

 grown in India, where it is called by the natives 'kole-roga,' 

 or black rot. It has since been found on coffee from Vene- 

 zuela and from Trinidad. It is also said to attack the betel- 

 nut palm in India. The injury is caused by a fungus called 

 Pellicularia koleroga (Cooke), which forms a thin, glairy, 

 whitish film on the under surface of living leaves. The film 

 is quite smooth to the naked eye ; when moistened it can be 

 removed as a delicate layer resembling gold-beater's skin, and 

 appears to have no organic attachment to the leaf, but simply 

 rests on the surface after the manner of the black fungi that 

 feed on honey-dew, and form a removable, black film on the 

 surface of leaves on which aphides have deposited honey-dew. 

 In India the disease makes its appearance about July, when 

 the leaves of the trees become covered with a slimy, gelatinous 

 matter, turn black, and fall. The berries likewise rot and fall 

 in clusters. 



When a portion of the film is examined under the micro- 

 scope, it is found to consist of a densely interwoven felt of 

 colourless hyphae embedded in a mucilaginous matrix ; the 

 spores are 6-5-7-5 /x, hyaline, minutely warted, and apparently 

 attached latterly to the hyphae. It is, however, necessary 

 that the fungus should be again investigated in a living condi- 

 tion, before any clear idea of its structure or affinities can be 

 arrived at. 



No remedial measures have been tried, except sulphuring, 

 so far as I am aware. Probably Bordeaux mixture or other 

 solution would be of value, as the fungus is superficial, as in 

 the Erysiphaceae. 



Cooke, M. C, India Office Report on Diseased Leaves of 

 Coffee and other Plants (1896). 



MERIA (Vuill.) 



Conidiophores emerging in small tufts through the stomata, 

 springing from a black, sclerotium-like mass formed in the 



