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The experiment was conducted in the same manner as the others. The germination 
of the dcidiwm spores was tested by placing some upon a glass slide in a drop of 
water, and keeping them in a damp atmosphere. They did not germinate for 48 
hours, and then only very feebly. I noted at the time: ‘‘ Very faint attempts at 
gerinination have taken place; the contents of the slide were placed at 10 a.m. to- 
day (July 11) on the leaves of the infected plant. I think this experiment must 
fail, so weakly have the spores germinated.” Notwithstanding this, however, by 
the 26th day both the infected and the check plants had Uredo upon them. 
The hope of demonstrating unequivocally the truth of the hetercecism of 
Puccinia graminis had by this time become so seriously imperilled, that I deter- 
mined upon varying my method of procedure. One hardly ever sees every in- 
dividual plant in a state of nature, infected with the same parasitic fungus, and it 
occurred to me that by keeping my check plants covered by bell glasses they were 
debilitated, and so rendered unduly liable to be attacked by the Uredo. I therefore 
determined to grow my check plants naturally, and only to cover my infected 
plants for as short a time as was compatible with the period necessary for free 
germination to take place in the cidium spores; after they had been placed upon 
the leaves. My supply of Meidium berberidis now failed, and I had to procure 
the fresh spores from Narborough, distanced about nine miles by rail, where 
several barberry bushes grew about a mile from the station. 
EXPERIMENT V.—On the 26th July, ten wheat plants were infected with 
Aicidium berberidis spores from Narborough, and ten similar wheat plants, grown 
from the same seed, selected as check plants. These latter were never at any time 
covered by any bell glass, and were planted about six inches apart, some 30 yards 
from where my other experiments had been performed. On the 16th day three of 
the infected plants had Uredo upon them; on the 25th day the experiment was 
concluded. Five of the infected plants had Uvedo on them, and nine of the 
checks. 
EXPERIMENT VI.—On the 26th July, seven wheat plants (two of which were 
only half an inch high, with unexpanded leaves) were inoculated with Acidium 
spores from Narborough, and seven wheat plants selected for check plants, which 
were never covered. The ecidiwm spores germinated freely upon a glass slide. 
On the 17th day Uredo appeared on the five oldest of the infected plants. On the 
24th day the experiment was concluded. There were then five infected plants 
with Uredo upon them (the two youngest having escaped), and seven check plants 
with Uredo upon them. 
ExpERIMENT VII.—On the 29th July, five wheat plants were inoculated with 
Aicidium spores from Flitcham (distanced eight miles), and a similar number of 
check plants selected. On the 12th day Uredo was observed on the five infected 
plants, and upon two, possibly upon three, of the checks. 
Experiment VIII.—On the 29th July, four wheat plants were infected with 
Aicidiwm from Flitcham, and a like number of check plants selected. On the 9th 
day all the infected plants had Uredo on them, as had three of the check plants. 
EXprRIMENT IX.—On the 1st August, four plants were infected with dcidiwm 
