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the germs of the disease gained entrance to the interior of the . 
branches through the newest growth of the young shoots and the 
central parts of the flower, especially the moist nectariferous sur- 
faces, and for the most part not later than the middle of May. It 
had consequently taken more than a month for the disease, after 
gaining entrance, to make sufficient headway to kill enough of the 
leayes to render the injury conspicuous; a result entirely in accord 
with the observations made on the slow progress of the disease in cool 
weather, and the long time leaves may remain green after the limb 
on which they are seated is black with the disease. The generali- 
zation is warrantable from these and other published facts that, as a 
rule, the trees are attacked in spring, and the disease passes through 
a period of incubation of a month or more before becoming suffi- 
ciently conspicuous to attract attention, that in exceptional cases 
where shoots still continue to push out vigorously, or through the 
agency of insects,the attack is later in the season, possibly as late as 
midsummer. 
In order, if possible, to secure some data in regard to the rela- 
tive action of blight upon different varieties of pear, the following 
careful experiments were performed. On July 15 half a pear from 
each of these several varieties—Bartlett, Beurré d’Anjou, Buffum, 
Doyenné Boussock, Duchesse, Flemish Beauty, Mount Vernon, 
Seckel and White Doyenné—was laid upon a plate with a very little 
water, and all placed under a bell jar. A drop of watery infusion of 
blighted pear was then placed on the cut surface of each. Two 
days afterward the spot touched by the drop in each was brown, and 
on the Beurré d’Anjou, Doyenné Boussock and Mt. Vernon 
were a number of beadlike, milky drops, which in three days longer 
had become a few large drops. The other varieties now had the 
brown spot somewhat enlarged, sunken, and covered with dew-like 
drops the size of a pin head. Three days later and the relative con- 
dition was the same. In looking about for an explanation of the 
divergent action of the three varieties, it was soon found—in plac- 
ing the half pears on the plate three would nof lie level and they 
were unwittingly trimmed on the lower side, which enabled them 
to absorb more water from the plate to meet the requirements of the 
bacteria. — 
A like experiment was begun July 18. This time a slice half an 
inch thick from each variety of fruit, made with the most. scru- 
pulous care to have all cut alike, was placed on a plate with water 
and under a bell jar as before. Beside the varieties used in the last 
experiment there were added Keiffer, Lawrence and Sheldon, being 
twelve in all. ‘To make the inoculation thoroughly uniform each 
was touched once with the point of a pin carrying what would ad- 
here to it when put into the creamy portion of a blighted pear. 
Two days after the Keiffer showed no change, but all the others had 
a small brownish drop at the point of inoculation, and half a dozen 
or so colorless drops scattered within a radius of a quarter of an 
inch from it. No difference in the varieties could be seen, unless 
the Flemish Beauty and Sheldon were slightly less advanced. Three 
days later and the surface of each is covered with large drops, even 
as large as a pea, some of which have coalesced into still larger 

