[Vor. 8 
312 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
The relatively high percentages and the extended range of 
germination as related to hydrogen-ion concentration in a beet 
100} 
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4 22° 
ES — Ó— 
E wre 
E 60 
* 40 
Š 
4 
$ 20 
C 
5 t 9 /0 
Fig. 9. Aspergillus niger in 2 per cent bacto-peptone solution. 
decoction medium are very striking, and the extended range 
of germination in “water HCl or KOH” is equally striking. 
It would seem, therefore, that either the beet decoction might 
b 
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ho 
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e 
8 
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2 
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ee 
e of Germination 
L3 
m 
ee 
"a 
b 
wa 4 
xe 
d 
è 
N 
Aeren 
8 
- 
Fs 
lim — I 
Pa t 2 3 4 s 6 7 8 ? ^ 
Fig. 10. Aspergillus niger in Czapek's full nutrient solution. 
possess some stimulating substance, which is absent in the 
synthetic culture media, or else it might undergo changes in 
reaction during the process of spore germination. Germination 
