INTRODUCTION. 



General. — The fungus diseases of the West Indies may 

 be said to furnish no exception to the general statement 

 that the plant diseases of tropical countries are very 

 numerous, and apparently more formidable than those of 

 the temperate regions. Although there has been no actual 

 instance of an epidemic approaching in magnitude the 

 classical example furnished by the leaf disease of the coffee 

 plant in Ceylon in the years 1875- 1885, yet considerable 

 loss has been suffered from time to time owing to the 

 attacks of fungi. The best-known instance is probably the 

 " rind fungus of the sugar cane," Trichosphaeria Sacchari, 

 which did considerable damage to the sugar industry in 

 the years 1895-1900 ; second to this is Marasmius Sacchari, 

 " root fungus of the sugar cane," which was especially 

 prominent in Barbados in 1904; Diplodia cacaoicola, "die- 

 back and brown pod fungus of cacao," and Phytophthora 

 omnivora, " black pod fungus of cacao," have also caused 

 much damage to the cacao industry in the Islands. 



Several of the parasitic fungi of the West Indies have a 

 wide area of geographical distribution ; Diplodia cacaoicola 

 and Phytophthora omnivora have been reported to occur 

 practically wherever the cacao plant is cultivated, Trichos- 

 phceria Sacchari occurs in India, Java, Mauritius and 

 Queensland, Colletotrichum falcatu/n, " red rot fungus of 

 sugar cane," is known in India, Java, Hawaii and Queens- 

 land, Sphcerostilbe fLavidum, " leaf fungus of coffee," is 

 spread over tropical America, and many others are less 

 widely distributed. The diagram on the opposite page 

 indicates the distribution of some of the more important 

 parasites of sugarcane and cacao. 



The two most important plant industries of the W T est 

 Indies are the cultivation of sugar cane and of cacao; other 

 crops which are cultivated for export are banana, cotton, 

 orange, lime, coffee, and coconut, while others still, such as 

 eddoe, yam, sweet potato, breadfruit, and mango are grown 

 principally for internal consumption. Of these crops sugar 

 cane and cacao suffer more severely from the attacks of 

 fungi than any of the others ; and the fungus pests of cacao, 

 principally on account of the perennial nature of the plant, 

 are more difficult to cope with than those of the sugar 

 cane. 



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