New York AGRICULTURAL EXPERIMENT StTaTIon. 349 
as they occur on the hosts under consideration. ‘Those on apple 
and Japanese plum trees are the only ones where the average 
length is noticeably greater than the rest in the list. Cultures of 
Sphaeropsis from either apple or Japanese plum trees when inocu- 
lated into apple, pear, or quince fruits produce black rot and as is 
shown in Table II these cultures grow interchangeably on at least 
four species of trees. In each instance the fruiting bodies result- 
ing from the cross inoculations have the same characters as those 
that occur on the trees naturally. 
Since cultures of Sphaeropses from the different hosts produce 
black rot of fruit, one apparently as readily as another, it was to 
be expected that the different cultures would make similar growths 
when cross inoculations were made in the trees. Accordingly, 
apple, pear, plum, cherry, and quince nursery trees were planted 
in a plat on the Station grounds for inoculation experiments. 
Dilution plate cultures were made of the Sphaeropses from the 
different hosts and after spores formed, transfers were made to 
sterilized bean stems in test tubes. The inoculations were made 
by making a small incision in the bark with a flamed knife and 
inserting some of the pure cultures of the fungus from the test 
tubes between the bark and wood; then the wounds were covered 
with grafting wax. The work was done the last of May and first 
of June. 
Table II gives the plan of the experiment together with the 
results; and shows: (1) Kind and number of trees inoculated 
and number of inoculations made in each tree; (2) source of cul- 
tures with which inoculations were made; (3) growth of fungus 
where inoculated. 
