SO-CALLED GERMICIDAL PROPERTY OF MILK. LOD 
thrive in it, and, as the experiment shows, certain species 
dropped out quite rapidly during the first few hours. The 
number of acid producing species found in the fresh milk was 
unusually small in this experiment, and were mainly of the 
species Bact, lactis acidi (Leichmann). ‘These appeared in 
small numbers in the plates made from the fresh milk, together 
with a few miscellaneous acid organisms. The act. lactis 
acidi was the only species which increased in numbers, its 
growth being quite uniform and so rapid that at the end of 
twelve hours it constituted 60 per cent. of all the organisms 
present, and was the only acid to be found. A study of Table 
32 shows the same condition as has been brought out in the dis- 
cussion of Table 31, the principal difference in this case being 
the species of acid found in the milk. In the fresh milk the 
acids were made up of B#. /actis aerogenes, together with a 
number of miscellaneous species. The miscellaneous ones did 
not increase materially, while 2. dactis aerogenes increased 
steadily from the outset, where it comprised 15 per cent. of the 
total number, until at the end of twelve hours it made up 25 
per cent. of the organisms present, a much less rapid increase, 
it will be noticed, than was made by. Bact. lactis acidz, but 
nevertheless an actual and continuous increase from the very 
Stal tc 
These experiments would seem to show that while the num- 
ber of bacteria decreased to a greater or less extent during the 
first few hours, the decrease was simply a natural result of the 
fact that certain species which had gained access to the milk 
found it a poor medium in which to develop, and therefore dis- 
appeared; while the true lactic organisms, which find in milk 
conditions well suited to their liking, increased continuously 
from the very outset. These results would seem to warrant 
the conclusion, therefore, that there is no ‘‘ property or condi- 
tion’’ in the milk which is germicidal, the decrease in numbers 
being the natural result of ill suited environment. 
DISCUSSION OF GROUP II. 
This group, as previously stated, contains those experiments 
where both the total number and the number of acid producing 
organisms showed a reduction during the ses few hours, later 
