CHESTNUT BARK DISEASE. 303 
new to science. It was among the species described by him, 
since the relationships of many of them are now somewhat 
obscure, that we made a search for some fungus that might 
throw additional light on Diaporthe parasitica. In this search 
we asked the aid of Professor Farlow, whose knowledge of 
American fungi is unsurpassed, and who has some of the 
Schweinitzian specimens in his herbarium, and from him we 
first learned of the close relationship of the chestnut blight to 
Endothia gyrosa (Schw.) Fr. This fungus was first described 
by Schweinitz as Sphaeria gyrosa, from North Carolina on 
Fagus and Juglans. He sent specimens to Fries, a famous 
authority on fungi in Europe, who later recognized it as a 
European species, and finally placed it under a new genus, 
Endothia. This possible relationship of the blight was brought 
out for the first time in the writer’s Report (6) for 1908. 
Neither Farlow nor the writer had at that time examined the 
ascospore stage of the true Endothia gyrosa, so the exact 
relationship of our blight fungus to this species was not posi- 
tively determined, though the writer called attention to the 
fact that, so far as one could tell from the Cytospora stage, 
it was impossible to distinguish between Diaporthe parasitica 
collected on chestnut in America and Endothia gyrosa found on 
the same host in Italy. 
Previous to this, however, Rehm (61) had decided that . 
Diaporthe was not the proper genus for our chestnut blight, 
and had placed it under the genus Valsonectria, but had not 
questioned its identity as a new species or its relationship to 
Endothia. 
Von Hoéhnel (29) seems to have been the first to definitely 
state that Diaporthe parasitica was not distinct morphologically 
from Endothia gyrosa, for in the latter part of 1909 he wrote: 
“Diese Pilz ist in Rehm Ascomyc., No. 1710, ausgegeben unter 
dem Nahmen Valsonectria parasitica (Murr.) Rehm. Es ist ' 
aber nicht anders als E. gyrosa mit schwach entwickelten 
Stroma.” Since then Farlow (20), Shear (65), Saccardo, and 
Rehm, the last two in letters to the writer, have also decided 
that the chestnut blight fungus is not distinct morphologically 
from Endothia gyrosa (sometimes called FE. radicalis) of 
Europe. 
