Pr ©. 
New YorK AGRICULTURAL EXPERIMENT STATION. 17 
Even where the Macrophoma spore masses were not outwardly 
conspicuous it was often found that just beneath the loose outer 
bark, which peels off readily, there was an abundance of white 
“spores and mycelium. 
The Macrophoma was found associated with all stages of the 
canker (but not constantly), even with the very beginning of the 
canker where it was often the only fungus to be found. Small, 
dead, sharply delimited areas of bark one inch in diameter fre- 
quently showed multitudes of the exuded spore masses and noth- 
ing else. 
Since the spores of Macrophoma malorum are about the size 
and shape of the spores of Spheropsis malorum Pk. and differ 
from them only in being uncolored, the opinion has been ad- 
vanced that the former is only an immature stage of the latter; 
but we believe that the two forms are distinct species. It is 
true that immature Spheropsis spores are uncolored, but the 
colorless stage is quickly passed and when full grown they are 
generally colored; whereas the Macrophoma spores remain un- 
colored indefinitely after attaining full size. The fact of their 
expulsion in May is evidence of their maturity at that time, but 
they show no color. Moreover, Paddock” has seen the hyaline 
spores germinate so there can no longer be any doubt that the 
Macrophoma is distinct from Spheropsis malorum. 
It appears to us that Macrophoma malorum is parasitic upon 
apple bark, but Paddock’s' inoculations gave only negative re- 
sults. Ifitis a parasite the lesions formed by it are very similar 
to those of Spheropsis. 
Cytrospora CanKHr.—About the middle of May Mr. Paddock 
called our attention to dead patches of bark on several apple 
trees in the Station orchard and pointed out the fact that while 
the dead areas resembled those produced in the early stage of 
Spheropsis canker, they were, nevertheless, slightly different 
and were inhabited by a different fungus which proved to be a 
species of Cytospora. The affected patches were discolored, 
“Paddock, W. Bul. 185 of this Station, p, 212, 
eT. Cc. 
