i64 
AMERICAN JOURNAL OF BOTANY 
[Vol. 9, 
Inoculation and dry-weight determinations were carried out as before. 
The cultures were incubated at a temperature of 25.8° C. In table 2 the 
results at the end of four, seven, and fourteen days are shown. The pn 
values are the averages of determinations made at the beginning and end 
of the period. 
The results are expressed graphically in figures 2, 3, and 4. In general 
the curves are similar in form to the one obtained in the first experiment. 
^ 3 S 6 1 g 
Culture Solution 
Fig. 2. Hydrogen-ion concentration and growth of G. Sauhinetii on liquid media — 
phosphate series after four days. 
At the end of four days there is a definite minimum in the curve. After 
seven days the depression in the curve is more marked, with its lowest point 
at Ph from 5.5-6.0. In the most acid cultures slight indications of growth 
were noticed at this time, but the first culture showed no appreciable dry 
weight. It is interesting to note that in the most acid cultures there were 
formed a number of colonies, which fact would indicate a stimulation of 
phosphate series after seven days. 
