Mycelium of the Uredinee. 2 
similar circumscribed dead area surrounds those sori of 
P. annularis which are formed late in the year, and that 
it is by means of teleutospores contained in these sori that 
the fungus is reproduced in the following spring. 
The localized mycelium of the zcidiospores especially, 
has a powerful influence upon the chlorophyll, causing it 
to lose its green colour, and, as De Bary * has pointed out 
with &. cancellata, making it disappear entirely. The 
affected tissue is found to contain an immense number of 
minute starch granules, To such an extent does the 
development of starch take place, that in the Himalayas 
the natives eat the hypertrophied stems of Urtica parvi- 
folia, which are affected with 2c. urtice, on account of 
the abundant nutritive starchy material they contain. 
The hypertrophies are eaten just before the acidia open, 
and are said to resemble cucumber in flavour.t The 
affected places generally assume some tint of yellow or 
reddish yellow, more or less bright. In the Polygonee the 
spots are bright red or purplish (4c. rumicis,U redo bifrons). 
In other cases they are yellow, surrounded by a purplish 
or reddish border (4c. zonale, behenis), Ina few instances 
all colour is more or less discharged, and the spots appear 
whitish (4c. albescens, leucospermum). 
The mycelium of all species is by no means thus 
localized. With some Uredines, on the contrary, it per- 
vades the whole plant with the exception of its roots— 
stem, leaves, petioles, peduncles, and the upper part of 
the root-stock. De Bary{ has shown that when the 
mycelium of a Uredine can be traced into the perennial 
parts of the host-plant, it is itself perennial; thus with 
* De Bary, ‘‘ Brandpilze,” p. 73. 
+ Surgeon-Major A. Barclay, ‘‘ On Aicidium Usgicz,” ‘Scientific Memoirs 
by Medical Officers of the Indian Army ” (1887), p. 2. 
t De Bary, ‘‘ Neue Untersuchungen iiber Uredineen ” (1865), pp. 20, 21. 
