240 BOTANICAL GAZETTE. [Sept., 
count of its supposed relation to diseases of apple trees. My 
cultures seemed to point to a connection with some common Roe- 
refer later. Many have probably read the account of Prof. 
alsted’s experiment, in a recent number of the BoTraNnicaL 
GAZETTE, and, with the author’s consent, I will state briefly 
the result. Early in the season, specimens of Gymn. macropus 
were gathered and allowed to develop under cover, so that there 
need be no danger of mixture with spores from outside. e 
ra 
fection on parts of the tree which had not been covered. In 
time the wcidia appeared and proved to be what has usually been 
called Roestelia penicillata. 
