98 SEMI-CENTENNIAL OF TORREY BOTANICAL CLUB 
INTRODUCTION 
In a letter recently written by Professor F. S. Earle, the well- 
known botanist of Cuba, he says: “There is a very varied and 
interesting fungous flora here, but ‘collecting’ is not nearly as good 
as in the States. Field work is difficult, and many species are 
rare and local. I am curious to see how many rusts you have 
from here. There are really a great many, but it will take years 
to find them all." Professor Earle speaks with the knowledge of a 
mycologist, as he has to his credit some forty published papers 
dealing with mycological subjects, issued largely in the score of 
years between 1884 and 1904. Since becoming a resident of Cuba 
in I904 he has occasionally gathered specimens of rusts, and he 
took a prominent part in the rediscovery of the rare Prospodium 
plagiopus at San Marcos in 1909-1910, as stated under that 
species. 
The study of the Cuban Uredinales, or rusts, resulting in the 
present paper, has abundantly confirmed Professor Earle's state- 
ment. Although the first collections of rusts were made in Cuba, 
doubtless about 1840-45, by Ramon de la Sagra, a few added by 
Charles Wright in 1855-7, and by others from time to time, yet 
prior to I915 the known Cuban rust flora would not have much 
exceeded half a hundred species. During 1915 the junior author, 
who had come to Cuba the previous year from a residence of three 
years in Porto Rico, began to gather material with the intention of 
publishing in Spanish a pamphlet on the rusts of Cuba for the 
use of students of the native flora. On February 22, 1916, he 
wrote to the senior author that "I have apparently so much new 
material, or at least new hosts, that I can not handle the subject 
properly under conditions here." He then proposed a joint paper 
on the rusts of Cuba, in English of course, and the presentation 
here made is the result. 
A study of available material, together with all information 
which the authors have been able to collect, brings the present list 
of Cuban rusts up to 112 species, with 28 additional names of rusts 
belonging to the form-genera Aecidium and Uredo, which doubt- 
less largely represent additional species whose life histories are too 
