ALKALI-FOKMING BACTERIA FOUND IN MILK. 
13 
consequently this alkali formation would interfere with the reaction 
as a means for determining the dextrose fermentation. 
Table 4. — Reaction produced by the alkali-forming bacteria in dextrose and plain-extract 
broth. 
Culture No. 
Dextrose-extract 
broth. 
Beef- 
extract 
broth, 
14 days. 
Culture No. 
Dextrose-extract 
broth. 
Beef- 
extract 
broth, 
14 days. 
7 days. 
21 days. 
7 days. 
21 days. 
10. . 
C.c. 
+2.40 
+ .66 
- .04 
+ 2.40 
+ 1.60 
-1.00 
- .64 
- .94 
- .90 
- .06 
- .60 
- .94 
- .88 
- .58 
- .86 
- .94 
- .80 
+ 1.10 
- .74 
- .86 
+3.00 
+2.08 
- .80 
- .82 
- .50 
- .90 
- .80 
+ 1.94 
2+5.60 
- .70 
+ 1.86 
- .86 
- .64 
- .64 
C.c. 
+ 1.46 
+ 1.40 
+ .82 
+ .78 
- .96 
- .84 
- .88 
- .86 
- .70 
- .20 
- .74 
- .84 
- .90 
- .80 
- .74 
- .84 
- .88 
+2.46 
- .80 
- .90 
+ .76 
+1.58 
- .82 
- .76 
- .94 
- .96 
- .82 
+ .42 
2+4.46 
- .96 
+ 1.70 
- .94 
- .90 
- .80 
C.c. 
-0.39 
- .43 
- .29 
- .41 
- .37 
- .38 
- .40 
- .36 
- .30 
- .30 
- .30 
- .29 
- .30 
- .28 
- .38 
- .32 
- .42 
- .41 
- .41 
- .40 
- .49 
- .40 
- .29 
- .31 
- .39 
- .35 
- .39 
- M2 
- .28 
- .38 
- .37 
- .32 
- .34 
- .34 
128 
C.c 
+ 1.40 
- .84 
- .56 
- .76 
2 +5.36 
2+4.44 
- .88 
- .76 
+ 1.12 
- .88 
- .86 
-1.00 
+2.56 
- .80 
+ .93 
- .60 
- .50 
- .84 
-1.00 
- .72 
- .26 
- .20 
- .52 
+ 1.54 
- .44 
- .30 
- .50 
- .40 
- .90 
- .70 
- .84 
- .50 
- .16 
- .40 
C.c. 
-0.86 
- .92 
- .90 
- .82 
2+2.72 
2+4.76 
- .92 
- .82 
+2.88 
- .98 
- .94 
- .80 
+ .76 
- .86 
+ .44 
- .84 
-1.06 
- .96 
- .88 
- .76 
- .86 
+ .94 
- .76 
- .48 
- .20 
+1.66 
- .16 
- .32 
- .70 
- .80 
- .84 
- .52 
C.c. 
37 
12 
130. 
— .39 
31.. 
131 
- .38 
32 
49 
132 
59 
133 
2 — .40 
60 ; 
134 
2 .35 
61 
135 
— .39 
62 
138 
- .37 
39 
66 
137 
72 
138... 
- .32 
- .42 
- .29 
62 
73 
139 
101 
140. 
102 
141.. 
103 
142.. . 
.25 
104 
143. 
- .33 
- .34 
- .39 
- .39 
- .32 
- .32 
- .23 
- .47 
- .32 
- .44 
- .42 
- .41 
- .44 
- .38 
- .31 
- .53 
- .38 
- .35 
- .43 
- .37 
105 .'. 
144 
106 
145 
107 
146 . . 
108 
147 
Ill 
303 
112 
309 
113 
314 
114 
317 
116 
319 
117 
321 
118 
322 
119 
120 
326 
121 
340 
122 
353 
123 
354 
124 
356 
125 
361 
126 
362 
- .34 
Minus ( — ) signs indicate an alkaline change* in titration. 
Plus (+ ) signs indicate an acid change in titration. 
1 Change from control, in c. c. N/10 NaOH titrating 10 c. c. of medium. 
2 Produced gas. 
In order to avoid the complicating alkaline fermentation in extract 
broth, synthetic media were prepared which consisted of sodium- 
ammonium phosphate as the only source of nitrogen with dextrose 
as the only source of carbon. The media used had the following 
composition: 
Medium A. 
Sodium-ammonium phosphate grams. . 2. 
Dextrose do 10. 
Potassium chlorid do. .1 
Distilled water , cubic centimeter. . 1, 000 
The results of the fermentation of the dextrose in these media 
are shown in Table 5. The change in the hydrogen-ion concentra- 
tion during 14 days' incubation was used as a measure of thefermenta- 
Medium B. 
Medium C. 
1.5 
1.0 
3.0 
10. 
.1 
.2 
1,000 
1,000 
