BACILLUS COLI COMMUNIS. 445 
Escherich, to degenerative changes in the protoplasm. 
The colon bacillus does not form spores. There is 
nothing in the morphology of this bacillus which is 
characteristic or which may aid in its identification, 
for in this respect it simulates many other organisms. 
Colon bacilli. Twenty-four-hour agar culture. 1100 diameters. 
The colon bacillus stains readily with the ordinary 
aniline colors; it is quickly decolorized by Gram’s 
method. 
Biology. It is an aérobic, facultative anaérobic, non- 
liquefying bacillus. It is motile, but its movements 
are so sluggish that a positive opinion is often difficult, 
being exhibited often by one or two individuals, in fresh 
cultures, and at a high temperature only. These move- 
ments are produced by flagella, which may be demon- 
strated by Loffler’s method of staining, though not 
usually in such numbers as are seen to occur on the 
bacillus typhosus. 
