[Vor. 7 
284 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
Bacteria per cc. 
(Logs.) 
0° 
9.0 p Cr NP a pd 
* ee 
e” 
4 = ama c 
/ rm = a- — — e «o m 
7 4 Dy RN 
——. — 
Nar E eee 
8.0 X 
\, 
\ 
7.0 
| | 
6.0 \ 
5.0 \ 
PH 
4.0 
slo 
A pou. 
il iz. rn 
6.0 jy N 
: b 
f o ~ om™ 
7.0 es A US Pad S Pa A E akan A 
bh A = v e 
eee a 
8.0 —. a 
9.0 
Hours 0 48 96 144 192 240 
Fig. 11. Relation of growth to hydrogen ion concentration of Bacillus coli at 
No.1 ————— plain bouillon. 
No.2 -------- dextrose added at intervals. 
No.3 — — — — .3 per cent dextrose. 
No. 4 
— —.—. 1 per cent dextrose. 
