624 THE SMALLER FUNGI. 
have seen that the spermogones which accompany the cluster- 
cups in the _eidium, for instance, seem to have some inti- 
mate relation to them. There is another kind of the smaller 
fungi which, attacking grain, is known as Rust, and in sci- 
ence is called Uredo. But besides the U. rubigo, or Rust, 
on the grasses and grain, Dr. Curtis enumerates twenty-eight 
other species which attack other plants, and which have 
come under his observation. In other sections of the United 
States other species are found, and on the cultivated roses 
of the gardens, an European species, the Uredo rose, has 
fallen under my notice. Of this particular kind of Rust, our 
author says, “in the Uredines as well as other of the Conio- 
mycetes (in which the spores are the principal features), 
the same fungus appears under two or more distinct forms, 
not necessarily mere differences of age, but so distinct that 
they have been regarded (and some are so still) as different 
species belonging to different genera, often far removed 
from each other, and bearing different names. One plant 
(fungus), for instance, sprinkled over the under surface of 
a rose-leaf, like tumeric powder, has its mycelium, or root- 
like threads, penetrating the tissue, whilst bearing above its 
spherical golden colored spores. Its vegetative system a 
complete, and apparently its reproductive also: hence it 
seems to claim recognition as a perfect plant, and under the 
name of Uredo rose was so recognized, until microscopical 
investigation determined otherwise. Thus, it has been dis- 
covered that certain dark brown spots which appear later In ` 
the season, are produced upon the same mycelium; and are 
indeed, aggregations of more perfect and complex fruits of 
the same plant. Before this point was satisfactorily decided, 
the brown spores, which are borne on long stalks and are 
themselves septate, or divided by transverse partitions into $ 
complex fruit, received the name of Puccinia rosæ. At this 
period Uredo rose and Puccinia rosæ, or the yellow fungus 
and the dark brown fungus, were believed to be distinct 
different plants; now, on the contrary, they are believed to 

