26 Kingo Miyabe . — Macrosporium parctsiticum, Thum . 
APPENDIX. 
The material studied by Mr. Miyabe was sent to me by the 
Rev. George Tucker of Smith’s Parish, Bermuda. I visited 
Bermuda in January 1882, and at that time the onions were 
free from disease; but in 1886 I received a letter from 
Mr. Tucker, saying that a serious disease had attacked the 
onions, and he forwarded some diseased plants soon after- 
wards. I had expected that I should find either Peronosporci 
Schleideniana or the Urocystis common on onions in the 
United States ; but to my surprise no trace of either was seen. 
I noticed there was an abundance of Macrosporium par asiticum, 
Thumen. Early the following year more material was sent 
by Mr. Tucker, and, although a very large number of speci- 
mens was examined, with the rare exception mentioned by 
Mr. Miyabe, there was no trace of the Peronospora, a species 
readily recognised by its conidia, oospores, and characteristic 
mycelium. As in the material of the preceding year, the 
diseased plants were covered with Macrosporium . As Pero- 
nospora Schleideniana certainly does produce a serious disease 
of onions in Bermuda, as has been shown by Mr. Arthur 
E. Shipley, who visited Bermuda in 1887 for the purpose of 
studying the subject 1 ; and as, with a rare excepiton, all of 
the numerous specimens of diseased onions from Bermuda 
which I had examined with great care showed no trace of 
Peronospora , — the question naturally arose whether the 
Macrosporium was merely a fungus which had attacked plants 
previously suffering from Peronospora , as most botanists 
would suppose, or whether it might not of itself cause a 
disease of onions. It was for the purpose of settling this 
point, if possible, that Mr. Miyabe, at my suggestion, under- 
took his investigation from which the possibility that 
Macrosporium can grow on the tissues of living plants free 
from Peronospora seems to have been demonstrated. I 
should here like to express my thanks to Mr. Tucker for the 
material which he kindly furnished. 
W. G. FARLOW. 
1 Kew Bulletin of Miscellaneous Information, No. 10, Oct. 1887; also Proc. 
Camb. Phil. Society, vol. vi. Part 3 (1887). 
