94 



BACTERIOLOGICAL METHODS 



disease, is not practicable but we desire to give the following 

 tabulation showing the relationship between the different species 

 of the colon-typhoid group of intestinal bacteria in their behavior 

 with dextrose and lactose media. 



BACTERIA OF THE COLON-TYPHOID GROUP 



There are numerous other distinguishing characteristics be- 

 side those indicated in the above tabulation, as agglutinating phe- 

 nomena and behavior with other special culture media. It is 

 simply desired to indicate somewhat more specifically the lines 

 of research which were necessary to determine the identity of the 

 related species and varieties of intestinal bacteria. 



The Bacillus coli was isolated as early as 1884 from the feces 

 of a cholera patient, at which time this organism was supposed 

 to have some causal relationship to cholera. Later it was proven 

 that this bacillus was a normal inhabitant of the intestinal tract 

 of man and of other animals, being regularly present in their 

 excreta, and this discovery proved of the highest importance to 

 sanitarians as the presence of this germ in water supplies, in milk, 

 in mineral waters, etc., is generally regarded as evidence of 

 sewage contamination. The colon bacillus has been found in 

 sewage contamination, river water, in spring water, ice, milk, 



