50 PUCCINIA MALVACEARUM 
of P. Malvacearum is well known, though not usually interpreted 
in that way, see Fig. 29.) These “ end-conidia” do not form a 
short tube, to penetrate the cuticle of the host, but “ pour forth 
their protoplasm, as it seems, without the formation of an 
opening, through the plasma-connections of the outer wall of 
the epidermis of the host into an epidermal cell,” and so into 
the tissues where it vegetates till required. It also exists in 
the same state in the seeds of the infected plants. The fungus, 
he says, “passes from the plasmatic into the filamentous state 
just before the outbreak of the primary pustules.” It is clear, 
however, that the figures he gives do not prove what he asserts. 
Putting aside this purely supposititious and intangible 
method, the chief means of perennation probably lies in the 
fact that certain teleutospores produced at the end of the 
growing season have the power of lasting through the winter 
and germinating in the spring. Plowright, Massee and Tau- 
benhaus all agree in this: the latter (1911) kept infected 
leaves, gathered at Cornell University in the United States 
from the living plant on November 26th, both indoors at a low 
temperature and outdoors, and by testing spores taken from 
them at intervals from December to April found that they still 
remained germinable, though more and more slowly as time 
went on. 
Dandeno, however (9th Report Mich. Acad. Sci. 1907, p. 68), 
states that the fungus does not winter in the seeds; he tried 
seeds of diseased plants, carefully excluding infection from 
outside, and found that they all produced healthy plants. His 
experience also was that no teleutospores remained viable till 
the next spring, but that the fungus maintained itself the 
whole winter through on mallow plants in sheltered spots. 
These differences may be partly a matter of climate, and as 
regards the “seeds,” unless there were sori on them, they could 
hardly be supposed to carry the infection, even if they came 
from infected plants, except by the presence of “mycoplasm” 
or mycelium, neither of which has been proved. 
For this reason the chief means of preventing the disease 
(apart from using “seed” from uninfected plants) must be to 
gather and burn all dead leaves from the infested bed. When 
