1924 
WOLPERT—FUNGI AND H-ION CONCENTRATION OF MEDIA 65 
2.5-5.5 and increases it within the range 6.5-7.9. Тһе reaction 
Ри 6.0 remains close to the initial acidity. Some exceptions to 
this generality are found, for at 15? C. the acidity of the solutions 
in the Py range 4.5-5.5 is decreased, while in the remainder of 
the series the active acidity is increased. 
Polyporus adustus at all temperatures produces more growth 
and grows at a wider range of Рн in the peptone solution than in 
^ 
о . / 
75 à / \ 
\ 
= JS 
і 7 \ 
LJ / \ 
/ \ 
-508 / А 
СЁ „ Y n 
we / \ 
= 222 2 \ 
c. E^ \ 
— 25 а = 
г ~ ` 
M "cene * o ‘\ 
53 тере В * 
/ f ==- 25° “ 
/ . 
; 359 ‚\ 
| Т Т Т ! 
Рн 5 4 5 6 
Fig.9. Pholiota adiposa іп Richards' solution. 
the Richards’ solution. While this fungus shows much better 
growth in the peptone solution at 15? C. than at either of the 
other 2 temperatures, it grows less at this temperature in the 
Richards’ solution than at either 25? C. or 35° C. Here, however, 
the variations in growth for the different temperatures are not 
аз marked as they are in the peptone series. As there is no close 
correlation between the optimal P, for the two media, since 
they vary considerably with the temperature and with the 
solution, it is not possible to designate any definite range of Рн 
аз the optimum for growth of this fungus. 
