198 REPORT OF THE BOTANIST OF THB 
August 6-11, 1900, the week preceding the occurrence of the 
. Injury, was the hottest week of the season. It was also very dry | 
and most of the time windy. 
Later, the leaf scorch of pears was observed on a few trees 
in each of several other orchards, and we are informed that it 
occurred, also, on nursery trees of Kieffer at Dansville. 
Bopy Biient.—The so-called body blight of pear trunks which 
is described on page 301 of Bulletin 167 of this Station is very 
common throughout Western New York. By theans of inocula- 
tion experiments Paddock” has shown that this disease may be 
produced by the apple canker and black rot fungus, Spheropsis 
malorum Pk. The same writer observed that the fungus Macro- 
phoma malorum (Berk.) Berl. & Vogl. is also of common occur- 
rence on the dead bark on pear trunks, and stated his suspicion 
that it may play a part in the production of body blight. How- 
ever, his inoculation experiments with Macrophoma malorum, a | 
year later, gave only negative results.*4 
According to our own observations both Spheropsis malorum - 
and Macrophoma malorum occur abundantly on the trunks and 
branches of pear trees affected with body blight. The Macro- 
phoma certainly has the appearance of being parasitic and. Pad- 
dock’s inoculation experiments should be repeated before it is 
finally decided that the fungus is not a parasite. 
In order to determine if Macrophoma malorum is an immature 
stage of Spheropsis malorum a pear branch thickly covered with 
fruiting pycnidia of Macrophoma was kept under observation 
from early May until September.* The spores remained hyaline 
to the end of the period, indicating that the Macrophoma igs not 
a stage of Spheropsis, but a distinct species. This conclusion 
is in harmony with Paddock’s observations on Macrophoma 
malorum® in cultures. 

“Paddock, Wendell. The New York Apple-tree Canker. Bul. 163 of 
this Station, pp. 184, 203. 
eG: 
“Bul. 185 of this Station, p. 212. 
eT. @. 
