372 
Journal of Agricultural Research 
Vol. VIII, No. io 
In the next series (series 4) the com used was from the same green¬ 
house plot as the preceding. The use of the same tools, etc., a week 
later, gave opportunity for a much larger inoculation with acid-forming 
bacteria. This is evi¬ 
denced by the data 
shown below. In this 
series bacteriological 
counts of some of the 
samples were made. 1 
The technic used was 
as follows: The sample 
was ground in a sterile 
mortar for 15 minutes, 
50 gm. weighed out, 
placed in a liter flask 
with 500 c. c. of sterile 
water and shaken 100 
times. One c. c. was 
plated in various dilu¬ 
tions in a yeast-extract agar and incubated for 48 hours at 37 0 C. 
Data on this series are given in Table VI. 
Table VI.— Series 4: Formation of acids and alcohol, disappearance of sugars , amino 
nitrogen , and bacterial counts in silage 
[Data all on ioo c. c. of juice, except bacterial counts.] 
Fig. 7.—Curves showing the increase in amino nitrogen and ammonia 
nitrogen in series 2. 
Age of silage. 
Total 
acidity 
(Nfro). 
Volatile 
acidity 
( Nfio ). 
Alcohol. 
NH a -N. 
Total 
sugars. 
Disappear¬ 
ance of 
sugars. 
Bacteria per 
gram of silage. 
Days. 
0. 
i ... 
1 . 
2 .. 
3 . 
4 . 
6. 
9 . 
C. c. 
1 5 ■ 5 
39 * 0 
55 - 5 
121. 0 
156. 0 
148. 5 
223. 5 
254.0 
C. c. 
2.7 
3-5 
4. 6 
7 * 1 
j8. 9 
24. 5 
47. 8 
58. 2 
Gm. 
O. OOI 
. 109 
. 176 
. 192 
• 193 
. 182 
. 197 
.268 
Gm. 
O. 028 
. 058 
. 076 
. 108 
. 120 
. Il6 
. IOI 
. 107 
Gm. 
6. 662 
7.036 
7 - 594 
5 - 030 
3 - 764 
4- 636 
2. 324 
2. 190 
Gm. 
0 
- -374 
~ .932 
(+)i. 632 
'2. 898 
2. 026 
4.338 
4.472 
9, 900, OOO 
106, 500, 000 
119, OOO, 000 
38, 800, 000 
106, 000, 000 
It should be noted that the preliminary increase in sugars occurs as it 
did in series 3. The comparatively small bacterial count in the 4-day-old 
silage is reflected in the total acid, amino nitrogen, and sugar columns. 
The alcohol curve (fig. 8) shows the same enzymic form as before. The 
acid curves (fig. 9) show the usual bacterial form. The amino-nitrogen 
curve (fig. 10) is of the enzymic form as before. The curves showing 
the disappearance of sugar in series 3 and 4, though not reproduced here, 
approach the bacterial form. 
1 Acknowledgment is gratefully made to Dr. R. E. Buchanan for the use of laboratory facilities and 
media for making these counts. 
