IN THE SEED WHICH ACCOMPANY GERMINATION. 
47 
2. 1 Vhai is the medium most suitable for its action f 
In the germinating seed, as already stated, the reaction was acid, the depth of tint 
given to very sensitive litmus paper being about the same as that caused by ’2 per 
cent. HC1. As the tryptic ferment in the pancreas requires an alkaline medium for 
its activity, experiments were made to test whether this one worked best in an 
alkaline fluid. Six tubes were taken, of the same capacity, and into each was put a 
measured quantity of boiled swollen fibrin. The tubes were labelled A, B, C, D, E, F, 
and to the fibrin in each was added as under:— 
A. 50 c.c. ‘2 per cent. HC1 and 5 c.c. ferment extract. 
B. 50 c.c. *4 per cent. HC1 and 5 c.c. ferment extract. 
C. 50 c.c. 1 per cent. HC1 and 5 c.c. ferment extract. 
1). 50 c.c. 1 per cent. Na 2 C0 3 and 5 c.c. ferment extract. 
E. 50 c.c. 1'5 per cent. Na 2 C0 3 and 5 c.c. ferment extract. 
F. 50 c.c. '5 per cent. Na 2 C0 3 and 5 c.c. ferment extract. 
Three control tubes were also prepared, containing no ferment extract.— 
G. 50 c.c. '2 per cent. HC1. 
H. 50 c.c. - 4 per cent. HC1. 
I. 50 c.c. 1 per cent. Na 3 C0 3 . 
To each of the latter an equal amount of fibrin was put, as in the first six. After 
24 hours, and again after 48 hours, they were examined, with the results given in the 
subjoined Table. 
After 24 hours. 
After 48 hours. 
A (‘2 per cent. HC1) . 
Digestion most active. Most peptone formed 
Fibrin all gone 
B ('4 per cent. HC1) 
Digestion begun. Less active than A . 
Fibrin about half gone 
0 (1 per cent. HC1) 
Digestion begun. Nearly as fast as B . 
About as B 
D (1 per cent. Na 2 G0 3 ) . 
No change in fibrin, except that it bad lost 
translucency. No peptone formed. A little 
alkali-albumin present, due to the Na.,CO., 
No further change evi¬ 
dent 
E (15 per cent. Na„C0 3 ) . 
As D. 
As D 
F ('5 per cent. Na^COA . 
As D. 
As D 
G. 
No change, but formation of a little acid-albumin 
by the acid 
No further change 
H. 
As G. 
No further change 
I. 
No change, except that fibrin was shrunken and a 
little alkali-albumin formed 
No further change 
Another set of tubes, prepared similarly, confirmed these results. The medium in 
which the ferment acts most advantageously is therefore a weak acid, about equal to 
'2 per cent. HC1. 
