THOMPSON YATES LABORATORIES REPORT 
With regard to the relationship of the Bacillus coli to the Bacillus enteritidis 
sporogenes, it has been found that very frequently the two organisms do not occur 
together. The significance of this is important as throwing light upon the significance 
of the Bacillus enteritidis sporogenes as an index of pollution. Where the Bacillus 
coli and Bacillus enteritidis sporogenes occur together this would be strong evidence 
that the Bacillus enteritidis sporogenes was of recent intestinal origin. But in a very 
large number of cases the Bacillus enteritidis sporogenes occurs alone. In these cases 
it is very hard to say what importance is to be attached to its presence, and unless 
an inoculation test of the virulence of the Bacillus is made, it would be impossible to 
say whether the Bacillus is enteritidis sporogenes or butyricus. 
W T hen dealing with a very large number of food-stuffs, it very greatly 
increases the work if the pathogenicity of the Bacillus which is isolated has to be 
tested each time. 
Table showing the frequency with which the Bacillus coli and Bacillus 
enteritidis sporogenes occur alone and together in five hundred and sixty samples 
of milk analyzed. 
Date 
Number of 
Samples 
Bacillus coli 
alone 
Bacillus enteritidis 
alone 
Together 
January 
45 
5 
I 
February 
+ 5 
I 
3 
I 
March 
55 
2 
1 1 
3 
April 
+ 1 
3 
'3 
3 
May 
5° 
4 
9 
3 
June 
+8 
3 
2 
July 
44 
1 
6 
August 
45 
1 
5 
September 
44 
4 
October 
57 
4 
2 
2 
November 
4° 
1 1 
2 
December 
46 
15 
