New York AgericutturaL Experiment Station. 353 
The extent of growth of the Sphaeropses where inoculated has 
been expressed in the relative terms, slight, fair, good and very 
good. Figures 1, 2 and 3 of Plate XX XI are reproduced from a 
photograph of inoculated nursery trees of apple, pear and Jap- 
anese plum respectively, and show what has been termed a very 
good growth. Figure 4 of Plate XX XI shows a slight growth on 
an apple tree, while Fig. 5 is a check apple tree. The other two 
degrees of growth range between the two shown in the illustration. 
Where the fungus made a very good growth it spread rapidly 
till the different inoculations coalesced and formed continuous 
eankers as is shown in the illustration. In some instances 
pycnidia formed by the tenth of July and by the first of August 
growth had stopped as could be seen by the formation of a defi- 
nite boundary between the dead and living bark. Pycnidia were 
now abundant on the dead bark and occasionally on the decorti- 
eated wood under the grafting wax as well as elsewhere on the 
dead surface. In some instances where the fungus made a less 
vigorous growth the area of dead bark was entirely covered with 
the wax. 
A number of the different cultures were inoculated into all four 
kinds of trees, all but three into both apple and pear trees, while 
all were inoculated into apple trees. Twenty-five sweet and 
twenty-five sour cherry trees, and twenty-five European plum trees 
were also used in the experiment, but none of the inoculations on 
these trees were effective. In all of the other inoculations there 
were but two entire failures. But the inoculations made with cul- 
tures of Sphaeropsis from cankered apple tree limbs made a 
greater growth than most of the others. Those made with cul- 
tures obtained from Japanese plum were the only ones which made 
a comparable growth. 
The results of the inoculations on the pear trees are interesting 
from the fact that the cultures obtained from cankered apple tree 
23 
