[Vor. 8 
204 
ANNALS OF THE MISSOURI BOTANICAL GARDEN 
Experiment 20.—The solution used in this experiment, with 
an initial P; 4.1, was that given above without the addition of 
acid or alkali. The growth of the 3 fungi is uniformly better in 
Dry wt P J Cc. 
à H odine 
T p 
o 
— 
O 
- is T 
lj RN m. zu 
lj 
Í 
/ 
0 ü 22 
[t] E] 8 12 16 20 
Ooys 
Fig. 10. Aspergillus niger on solution of initial Pa 5.9 containing 
thiosulphate. 
these cultures than where the thiosulphate is used at the same 
Py. This is rather markedly so for Botrytis which is most sus- 
ceptible to the inhibiting influence of the thiosulphate. The 
acidity produced by Aspergillus and Botrytis is also greater than 
that in any of the cultures of the 4 preceding experiments. 
The tests for sugar were made by adding a few cc. of Fehling’s 
