1900 | BOTRYTIS AND SCLEROTINIA 399 
was still fresh and sound. The bark 
appeared to be first affected, as it was 
always discolored somewhat in ad- 
vance of the wood. Upon examining 
the outward excrescences it was 
found that the dusty appearance of 
the surface was due to a dense 
growth of a form of Botrytis, much 
like cinerea, but not entirely agreeing 
with the typical form. The conidio- 
phores were very stout and thick, 
averaging 20m in diameter, and the 
conidia large and very various in 
shape, many being nearly 30 in 
length (fig. zo). In cultures the form 
at once reverted to the typical cinerea, 
Showing that it belonged to that 
Species. Further examination showed 
that these excrescences were a sort of 
half-formed sclerotia, having the usual 
cellular structure at the base, but 
lacking a definite surface layer and 
resolving above into a dense mass of 
conidiophores. Fig. go shows a sec- 
tion of one of these sclerotia. They 
originate in the cortical parenchyma, 
being separated by the bast layer from 
the wood. Besides these sclerotia the 
cortical parenchyma was found to be 
permeated by a vigorous mycelium 
about as in the other diseases des- 
ctibed. The affected tissue was being 
rapidly destroyed, but the bast layer 
‘Seemed to be little affected and no 
filaments could be found in the wood 
€xcept a few in the most outer portion. 
Fic. 3.—Linden stem attacked 
by Botrytis. 
