BOTANICAL GAZETTE. 145 
ance. 
It can scarcely be doubted that the protoplasm of a higher 
plant, such as a phanerogam, differs from that of a lower erypto- 
gam in being capable of doing more work, and that the great 
advantage derived, by a parasitie Fungus which has its life so 
adapted that it can tax the cells of a phanerogamous host plant, 
is that it contains its food materials in a condition more nearly 
approaching that of its own substance, than would be the case if 
ad to work these materials up from inorganic matters. 
Now it seems not improbable that the protoplasmic substance 
of a higher phanerogam may contain so much energy that it can 
hot only supply the vegetative mycelium of a parasitic fungus with 
all that it requires for its immediate growth, but also suffices to 
enable that fungus to store up enough energy in its asexual or 
@pogamous spores to last until the next generation of the fungus 
82ins its holdfast on another (and it may be distant) source of life- 
§lving substance. seauete 
et us take the case of a uredinous fungus parasitic In the 
leaves of a phanerogam. We know that the substances necessary 
for the whole growth of the phanerogam are formed in the cells 
Of the leaf; not only so, the matters which eventually find their 
Place in the reproductive organs must be formed there also, po- 
tentially at least. The leaf of a phanerogam so attacked, more- 
2ver, is able to support the parasitic fungus for a long time un- 
Wwured, as I have convinced myself by experiment, and there can 
no doubt that substances pass into the fungus which would 
ormally have passed into other parts of the host plant itself. 
ut we may imagine even this to fail after a time—we may 
