TUBERCLE BACILLI IN BUTTER 425 
80° acid in milk and 28° acid in whey. Bacillus bulgaricus had to pro- 
duce 208° acid in milk and 60° acid in whey. She quotes the work of 
other investigators as Bassenge, Behla and others that lactic acid is 
toxic for Bacillus typhosus. Krumwiede and Noble (1915) report that 
the typhoid bacillus is killed in sour cream by acids and that the destruc- 
tion is proportional to the amount of acid and number of bacilli. Wash- 
burn (1908), in artificially infected milk found that B. typhz suffered no 
diminution in numbers up to twenty days. They had practically dis- 
appeared after forty-three days. Potter (1910) concluded that Bacillus 
bulgaricus and Bacterium lactis acidi exerted no appreciable repressing 
effect on Bacillus typht and that these organisms may not be depended 
upon to make milk, which has been contaminated, safe. 
TABLE NLV 
VIABILITY OF TYPHOID BACILLI IN SOUR CREAM 
(Krumwiede and Noble) 
Days o 2} 7 | 8 | 9 | wo in 
Reaction * 10% 22% 5% 10% 
Number of typhoid 
bacilli. . . | 892,000 85,000,000)800.000,000 278,000,000 181,000} 400 
* Number of cubic centimeters of N alkali needed to neutralize 100 ce of cream 
Molds in Butter. Thom and Shaw (1915) found that mold in 
butter usually took three forms: first, orange yellow spots produced 
by Oidium lactis; secondly, dirty green spots produced by cladosporium 
alternaria, thirdly, green spots which are caused by penicillium. <A 
salt content of 2.5 per cent prevented the development of the above 
fungi and, therefore, their presence indicates a low salting. The pres- 
ence of much curd was stated to allow a more vigorous growth of mold. 
Hastings (1916) has recommended that butter tubs and liners be placed 
in boiling water heated to 150° to kill the mold spores. 
Tubercle Bacilli in Butter. While the literature on the spread of 
this disease by butter is not extensive, there are several important 
investigations on the question. Rosenau, Frost and Bryant (1914) 
examined twenty-five samples of Boston market butter and found tuber- 
ele bacilli in two of them, B. coli in six and streptococci in fourteen. 
Hill (1911, 1913) has reported the spread of typhoid fever and diph- 
theria by butter. M. Mohler, Washburn and Rogers (1909) found that, 
contrary to prevailing opinion, tubercle bacilli were not devitalized by 
