In all of the sour hams which were examined bacteriologically a large
anaerobic bacillus was found to be constantly present. From several
of the hams this bacillus was obtained in pure culture; that is, it
was the only organism present in cultures made from the sour meat and
from the bone marrow of the femur. Such cultures, when held at room
temperature, gave, at three days, a sour-meat odor exactly resembling
that obtained from sour hams.
In many of the sour hams other bacteria were found in association with
the anaerobic bacillus noted above. These other bacteria, however, were
not constant, being sometimes present and sometimes absent. Among the
other bacteria noted in the sour hams, the following forms occurred
most frequently:
1. A nonmotile, gram-positive bacillus, measuring from 1.5 to 4 microns
in length by 0.5 micron in breadth, sometimes in chains and filaments.
2. A small, nonmotile, gram-negative bacillus, about the size of
_Bacillus coli_ and usually in pairs.