CHAPTER III. 

 BACILLUS COLI COMMUNIS. 



THE Bacillus coli was first isolated from human feces 

 in 1885 by Emmerich, who thought that it was the spe- 

 cific cause of Asiatic cholera. Many investigators have 

 since studied its peculiarities, until at the present time 

 it is one of the best-known bacteria. 



It is habitually present in the fecal matter of most ani- 

 mals except the horse, and in water and soil contaminated 



FlG. 109. Bacillus coli communis, from an agar-agar culture; x IOOO (Itzerott 

 and Niemann). 



with it. With water or dust it gains entrance into the 

 mouth, where it can frequently be found, and occurs 

 accidentally in foods and drinks. During life the organ- 

 ism sometimes enters wounds externally from the surface 

 of the body or internally from the intestine, and is a 

 cause of suppuration or at least occurs in the pus. The 

 Bacillus pyogenes foetidus of Passet is almost certainly 

 identical with it. 



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