188 A Mushroom Disease. [Sess. 
It was quite evident that the fine mycelial threads growing 
on the top of the wort retained their vitality through the pres- 
ence of a thin film of air, the amount of disinfectant intro- 
duced being too small to drive it out and submerge the 
threads, yet, at the same time, it was possible that any 
conidia formed might be killed. I accordingly made sub- 
cultures from the tubes in which growth appeared to be 
arrested in experiment II. This was done as follows: The 
tubes were well shaken, to wash off as many conidia as 
possible, and a few drops of the liquid were transferred to 
sterile tubes. The results were as follows :-— 
Sub-cultures from II.a@ showed no growth in three weeks. 
" " II.6 W " " 
" un IL. showed growth in one tube. 
" u II.d no growth. 
The above experiments proved the efficacy of the copper 
solution and also the corrosive sublimate, when applied at a 
strength of z455 OF ae4yp 28 a means of destroying the 
spores. The Scottish Mushroom Company have decided to 
use corrosive sublimate for disinfecting the tunnel, and prep- 
arations are being made for spraying the whole place with it. 
My thanks are due to the President of the Society, Drs 
Davies, J. Taylor Grant, and Mr G. T. West, for valuable 
suggestions made and assistance rendered during the time the 
investigations were in progress. 
Nott, May 1901.—-Since this paper was read the tunnel 
has been sprayed three times with corrosive sublimate, the 
strength of the solutions used in the three sprayings being 
ts00’ Too and sdo respectively. When the spraying was 
completed tests were made in various parts of the tunnel. 
1. Sterilized plates were exposed for periods of one, six, and 
twenty-four hours, and out of thirty plates only two 
showed any sign of growth in seven days. These were 
exposed at the mouth of the tunnel, and developed 
numerous bacteria as well as blue mould. 
2. Thirty samples of soil were selected, some from the 
surface, and others at various depths down to 12 
inches. These were treated in the same manner as 
