25 



of 40 species to the known West Indian flora, bringing it up to a 

 total of 214 species. 



This much for statistics, in which the islands of Haiti (His- 

 paniola) and Jamaica, the second and third largest of the West 

 Indies, with their highly varied topography and climate, have 

 an insignificant part. It can be said that the rust flora of Cuba 

 and Porto Rico, the largest and the smallest of the four large 

 islands, is about as well known as that of many of the states of 

 the Union, but that Haiti and Jamaica are practically virgin 

 territory, yet awaiting the rust collector. None of the smaller 

 islands has yet been explored to any extent for rusts. 



The area of the Greater Antilles, embracing the four large 

 islands, lies just within the tropical zone, and a long way from 

 the equator. Its relation to the equator is about the same as 

 that of the region about Rio Janiero, Brazil, and it is with 

 the rust flora of this region that the greatest similarity is 

 shown . 



The four islands range through a latitude of five degrees, or 

 about the same as that of the state of Illinois or New York. It 

 can not be expected, therefore, that their individual rust floras 

 should show any large differences. W^hile there is yet not enough 

 known to justify close analysis, still it is clearly evident that the 

 Cuban flora favors that of North America, having many char- 

 acteristic species in common with southern Florida, Mexico and 

 Central America, while the Porto Rican flora favors that of 

 South America, with species in common with Venezuela, Colom- 

 bia and southward. 



Comparing the rust flora as a whole with that of temperate 

 regions the most interesting feature is the adaptation of the 

 several methods of spore propagation to climatic conditions for 

 the maintainance of the species. About 65 per cent of the known 

 species appear to propagate almost or quite wholly by uredinio- 

 spores. These include not only tropical species, but many that 

 in temperate regions commonly produce teliospores and complete 

 their life cycle, such as Uromyces appendicidatiis on the legumes 

 and Puccinia salviicola on the labiates. Only about 10 per cent 

 of the long cycle species make use of their full complement of 



