138 Dr. J. White. [Sept. 6, 
present, but no signs of bacteria were visible, so that it seems most probable 
that the digestive fluid exerts an antiseptic action. 
Since the above was written, Prof. Vines was so good as to give me the 
benefit of certain suggestions and criticisms during a visit made to England, 
and these were such as to render it advisable to repeat certain of the 
experiments under different conditions and with varying controls. For this 
purpose Drosera Whittakeri was selected. | 
Prof. Vines suggested that the strong chloroform used as an antiseptic 
might exercise an inhibitory effect on the enzyme action. To ascertain if 
this were the case, the experiments were repeated just as before, with the 
exception that 4 drops of 0°1-per-cent. HCN were added to each 100 c.c. of the 
digestive solution in the test-tubes, in place of the chloroform previously 
employed as an antiseptic. After leaving the test-tubes for 40 hours in an 
oven at 32° C. I found that the same results were arrived at as before, 
i.e. that marked fibrin digestion had occurred, but no trace of any digestion 
of peptones could be detected. 
Prof. Vines further mentioned that the reaction of the digestive solution 
might affect the activity of the enzymes present init. In order to test this 
point, the second additional series of experiments was performed. The 
freshly made digestive solution was found to be neutral, and into each of 
12 test-tubes (A—L) was poured 100 cc. of this neutral solution, and four 
drops of 0:1 per cent. hydrocyanic acid. The contents of each test-tube were 
then treated as follows :— 
The contents of test-tubes A, B, C, D, were left neutral. The solution in 
B and D was boiled. To A and B was added a little well washed fibrin. To 
C and D a small quantity of Witte peptone was added. The contents of 
E, F, G, and H were acidified by the addition of a few drops of 0°2-per-cent. 
hydrochloric acid. The solution in F and H was boiled. To E and F fibrin, 
to Gand H Witte peptone was added. The contents of I, J, K, L were 
rendered alkaline by pouring into each test-tube a few drops of a 1-per-cent. 
solution of sodium carbonate. The solution in J and L was boiled. To I and 
J fibrin, to K and L Witte peptone was added. 
The test-tubes were then plugged with sterilized cotton wool and put into 
the oven at 32°C. as before. After 40 hours the contents of all the test- 
tubes were tested and it was found that A, E, and I all gave a strong peptone 
reaction, the strength of which was apparently the same in each; B, F, and 
J gave a faint peptone reaction of the same strength as the original freshly 
made solution exhibited, showing that in these boiled samples, no further 
protein digestion had taken place. 
