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THE SOUTH AFEICAN EXIST FUNUI. 
I. The Species of Puccinia on Compositae. 
By L B. Pole Evans. 
(From the Botanical Laboratories, Union of South Africa, Pretoria.) 
(Read August 18, 1915.) 
(Plates XLV-XLIX.) 
The following descriptions and accompanying notes are based mainly 
upon material which the author and his colleagues have collected during the 
past ten years in South Africa, and which is now represented in the Myco- 
logical Herbarium of the Union of South Africa at Pretoria. 
The material has been collected primarily with the object of elucidating 
the life-histories of the various rusts which are so destructive to many of 
our economic crops, and it is hoped that the descriptions of these parasites, 
of which this is the first instalment, may promote a more widespread 
interest in this group of plants and may be the means of adding consider- 
ably to our present very imperfect knowledge of these fungi. 
What has hitherto been published on the South African rusts is very 
largely due to the labours of MacOwan in the Cape, and Medley Wood in 
Natal. The greater portion of the material was culled from the collections 
of these two botanists, and from botanical collectors who visited the country 
from time to time. 
The descriptions of practically all the species were consequently pub- 
lished by European mycologists in scientific journals of European origin, 
many of which are not obtainable in South Africa to-day, and in many 
instances the descriptions were based on scanty and immature material. 
It will not be surprising, therefore, to find that the number of species 
occurring in South Africa must be considerably added to, v/hile existing 
species may require amending. 
The descriptions of the species in this and following contributions will 
in the main be those of P. and H. Sydow's Monograijhia TJredinearum; 
although I shall not scruple to amend them from my own observations 
whenever this may appear necessary. I also propose to follow the arrange- 
ment of species as is done by P. and H. Sydow in the above-named work. 
For descriptions of new species I alone am responsible. All the species 
