A MONOGRAPH 
OF THE 
BRITISH 
UREDINEA! AND USTILAGINEA?. 
CHAPTER. I. 
BIOLQGY OF THE UREDINEAZ/—INTRODUCTORY REMARKS. 
THE Uredinez constitute a large and important group 
of parasitic fungi, affecting honey plants and ferns, 
representatives of which are familiar to every student of 
nature, practical agriculturist, and working microscopist. 
In whatever part of the world phanerogams appear, these 
parasitic cryptogams accompany them. 
Our present object is to obtain an insight into. the life- 
history and the structure of those species which are known 
to occur in Great Britain, Much has been elucidated con- 
cerning these points during the past twenty years, but still 
much remains to be discovered. 
They all grow as parasites upon some living plant, 
independently of which they cannot exist, and consist 
of two essential elements—spores and mycelium. 
The spores every one sees; the mycelium, on account 
of its inconspicuous nature, and because it cannot be seen 
without some little effort, no one takes the trouble to look 
B 
