1921] 
319 
WEBB—GERMINATION OF SPORES OF CERTAIN FUNGI 
A. niger exhibits a relation to hydrogen-ion concentration 
similar to that of B. cinerea. Maximum germination is furnished 
vy / j 
p 7 t 
f. N 
; / | 
Feo / X 
à ] i 23% 
LR ] s 
F[ fj 
$ Ej 
? 20 r 
d | 
+ 5 é 7 8 9 " 
3b 
M 
b 
i 
Fig. 16. Penicillium cyclopium in sugar beet decoction. 
between Py 3.0 and 4.0 in all media except beet decoction. 
Here the range extends from the mentioned concentration to 
Py 7.5. Low percentages of germination, except in beet decoc- 
tion, occur under conditions of active alkalinity. Clark found 
éo 
E 
* 
$ 
$ Ise 
* 23% 
> —L - ——d - 27% 
Ya 
E 
M» CN 
A^ - y^ 
EN B - re a 
BRUT mAVCNEC (€ 
Å A a ee yd ee 
fy 2 3 + s 6 8 9 /a 
Fig. 17. Penicillium italicum in M/5 mannite solution. 
that the spores of Aspergillus flavus were somewhat more re- 
sistant to the various acids and alkalis in beet decoction than 
were those of “Botrytis vulgaris." The results presented in 
this paper for A. niger and B. cinerea further substantiate this 
relation, and the data obtained for the former in solutions of 
