58 British Uredinee and Ustilaginee. 
CHAPTER VIII. 
MYCELIUM OF THE USTILAGINEZ, 
THE vegetative mycelium of the Ustilaginee is to the 
parasite one of its most important organs, for by it, and 
by it alone, does the fungus derive its nutriment from the 
host-plant upon which it subsists. Yet the mycelium is 
of all parts that which is least frequently observed ; nor 
can this be wondered at when one remembers that, like 
the mycelium of the Uredinez, it can be seen only by 
careful search —by cutting and teazing out numerous 
thin sections of the host-plant. We owe most of the 
information we possess upon the mycelium of the Usti- 
laginee to Fischer von Waldheim,* although, among 
others, both Kiihnt and Hoffmann} had previously 
figured it. It exists most abundantly in the tissues 
of the host-plant, in the immediate vicinity of those 
places in which the spores are developed; but it can also 
be found in other parts of the affected plant—in the 
monocotyledons particularly in the stem, but especially 
in the nodes and in the root-stock. In the dicotyledons 
it is not so easily found at a distance from the spore-beds ; 
still, in them too it has been seen in the root-stock and 
* Fischer von Waldheim, ‘‘Pringsheim Jahrbiicher” (1869), vol. vii. 
pp. I, 2. 
+ Kithn, “‘ Krankheiten der Kulturgewichse,” 2 aufl. 1859. 
t Hoffmann, “ Ueber der Flugbrand.” 1866, 
