6i6 



Bacillus Coli 



Bacillus Coli Communis (Escherich) 



General Characteristics. — A motile, flagellated, non-sporogenous, aerobic aad 

 optionally anaerobic, non-chromogenic, non-liquefying, aerogenic, saprophytic, 

 occasionally pathogenic bacillus, staining by the ordinary methods, butnot by 

 Gram's method. It produces indol, coagulates milk, and produces acids and 

 gases from dextrose, lactose, and sucrose. 



This micro-organism was first isolated from human feces by- 

 Emmerich,* in 1885, who thought it to be the specific cause of 

 Asiatic cholera, and called it B acillus neapolitanus. Many have since 

 studied it until it has now become one of the best known bacteria. 



Distribution. — It is habitually present in the feces of animals, and 

 in water and soil contaminated by them. Soon after birth the 

 organism finds its way into the alimentary canal and permanently 



Fig. 254. — Bacillus coli (Migula). 



establishes itself in the intestine, where it can be found in great 

 numbers throughout the entire life of the individual. It is almost 

 certainly identical with Bacillus pyogenes fcetidus of Passet, and so- 

 closely resembles B. acidi lactici that Prescottf believes them to be 

 identical. It may also be identical with Bacillus lactis aerogenes, 

 Bacillus cavicida, and other separately described species. 



Morphology .^The bacillus is rather variable, both size and form 

 depending to a certain extent upon the culture medium on which it 

 grows. It measures about 1-3 X 0.4-0.7 /x. It usually occurs in the 

 form of short rods, but coccus-like and elongate individuals may 

 be found in the same culture. The bacilli are usually separate 

 from one another, though occasionally joined in pairs, are actively 



*" Deutsche med. Wochenschrift," 1885, No. 2.. 



t Society of American Bacteriologists, Dec. 31, 1902. 



