544 THE ANAEROBIC BACTERIA 
Toxin.— A toxin has not been demonstrated in cultures of B. tertius. 
The organism is not pathogenic for guinea-pigs. 
Bacteriological Diagnosis. — Mo/7j/?o%?/.— The long, thin, rod-shaped 
organism with spores in various stages of development is suggestive 
of B. tertius. 
Cultural.— The fermentative activity, and the absolute absence of 
proteolytic powers, as well as the moderate evolution of gas from utiliz- 
able carbohydrates is distinctive. 
Final diagnosis depends upon the absence of pathogenic powers for 
laboratory animals. 
BACILLUS BIFERMENTANS. 
Bacillus bifermentans (B. bifermentans sporogenes) was described 
by Tissier and ]\Iartelly^ as an anaerobic bacilhis whose fermentative 
powers are marked and which exhibits in addition rather striking pro- 
teolytic properties. Tissier- has found the organism in association 
with other bacteria in war wounds. Miss Hemple^ has also isolated the 
organism from pathological material and has given a complete account 
of its cultural characters. 
Morphology.— Bacillus bifermentans is a straight, rod-shaped organ- 
ism with rather square-cut ends measuring from 0.6 to 1 micron in 
diameter and from 4 to 7 microns in length. Curved forms are uncom- 
mon, except in old cultures, and involution forms are rare. Occasion- 
ally short chains of 4 to 6 elements may be found, however. In young, 
actively growing cultures the bacilli are large and thick; in older 
cultures the organisms are distinctly smaller. 
The organism is non-motile and flagella have not been demonstrated. 
Capsules have not been observed. 
Spores are readily formed in media containing no utilizable carbo- 
hydrates, but do not appear to develop in media undergoing fermenta- 
tion. The spores are rather large, although they do not exceed mate- 
rially the diameter of the vegetative cell, and are somewhat flattened 
at the ends, which gives them a distinctly oblong outline. Usually 
they occur at the center of the parent cell but they may be distinctly 
subterminal. The spores separate readily from the vegetative rods and 
occur free in the media. 
The freshly isolated organisms and young freshly isolated cultures 
retain the Gram stain, and color readily with ordinary anilin dyes. 
Older cultures are prone to degenerate; such organisms do not stain 
by Gram's method and the ordinary anilin dyes color them irregularly. 
Isolation and Culture. — B. bifermentans grows readily in the absence 
of oxygen upon solid media enriched with glucose or glycerin or with 
protein. The colonies are fairly regular, round, thicker in the center, 
and with thin edges. Submerged colonies are lenticular, regular in 
outline and without distinctive characters. 
1 Ann. Inst. Pasteur, 1902, 16, 865. ^ Ibid., 1916, 30, 681. 
3 Jour. Hyg., 1918, 17, 13, Organism No. II. 
