540 THE ANAEROBIC BACTERIA 
from the heart l)lood if the animal is killed after the paralysis is well 
marked. 
Until 1915 it was generally held that Vibrion septique, or B. oede- 
matis maligni, was rarely, if ever, an incitant of infection in man. 
The two cases of typhoid fever, which terminated fatally after invasion 
of the body by organisms morphologically similar to the Vibrion 
septique, reported by Brieger and F]hrlich,i were regarded as medical 
curiosities. 
During the World War, however, Vibrion septique was definitely 
shown to be nearly as formidable an incitant of gas gangrene in wounds 
as the gas bacillus, and there was comparatively little difference, both in 
their pathogenic and toxicogenic powers. Pure infection with Vibrion 
septique is practically unknown so far as human invasion is concerned ; 
consequently, the lesions in uncomplicated cases in man are unknown. 
Symbiosis of the Vibrion septique with B. sporogenes does not appear 
to result in so marked an exaltation of virulence of the Vibrion as that 
exhibited by the symbiosis of B. welchii with B. sporogenes. 
Bacteriological Bi&giiosis.— MorpJiologi/.— Motility.— The character- 
istic motility of the organism obtained from pathological fluids or from 
tissues (observed anaerobically) is an important point of distinction 
between this organism and the Welch bacillus. The Vibrion is a 
rather long, slender. Gram-positive rod, with clearly rounded ends. 
The citron and navicular degeneration forms, when observed in patho- 
logical material, are distinctive; their absence, however, is not indica- 
tive of the absence of the organism. 
Cultural Diagnosis. —The meat medium is reddened, but not 
digested. Some gas bubbles may collect at the surface of the fluid. 
The colonies are not characteristic, although deep colonies in agar, 
which are filamentous, should be suggestive. 
Serological Diagnosis.— The agglutination of the organism with spe- 
cific serum is strongly suggestive. It may be diagnostic. 
The injection of toxin into a guinea-pig or a rabbit and the injection 
of a second animal with a toxin-antitoxin mixture, the toxin being a 
filtrate of a forty-eight-hour culture under observation, is distinctive. 
The first animal should die and the second one should survive. 
Distribution.— The organism appears to be rather widely distributed 
in the soil and it is quite possible that the intestinal tracts of the herbi- 
vora will be found to be sources of contamination. The organism has 
been isolated from milk.^ 
BACILLUS FALL AX. 
Bacillus fallax was described by Weinberg and Seguin^ as a rather 
small, rod-shaped organism with rounded ends, measuring from 0.5 to 
1 Berl. klin. Wchnschr., 1882, 19, 661. 
2 Robertson: British Med. .Tour., 1918, i, 583. 
^ Compt. rend. Soc. de bioL, 1915, 78, 6S6 
