542 THE ANAEROBIC BACTERIA 
cooked meat media. The organism is not proteolytic, and somewhat 
indifferently fermentative. 
Toxin.— Weinberg and Seguin state that freshly isolated cultures of 
B. fallax contain a soluble poison which when injected intravenously 
(1 to 2 cc.) causes the death of guinea-pigs in from twelve to twenty- 
four hours. The same amount introduced subcutaneously causes the 
formation of a marked edema. Hemotoxins were not observed. 
Pathogenesis.— Freshly isolated cultures of B. fallax are patho- 
genic for laboratory animals but the pathogenic power is rather soon 
lost and cannot be restored readily by passage of the culture through 
animals. 
The injection of culture and toxin of the organism leads not only to 
a gelatinous edema but gas formation in the tissues as well, together 
with a sanguino-serous exudate which is richly infected with bacilli. 
The organisms are readily isolated from the heart blood. Spores are 
not formed in the animal body, or at least they have never been 
reported. 
B. fallax has been isolated from the blood stream of human cases. 
It is one of the gas gangrene group, although its pathogenic power for 
man and animals is less than that of B. welchii, Mbrion septique, or 
B. oedematiens. 
Antibodies.— Weinberg and Seguin have succeeded in inducing the 
formation of specific agglutinins for B. fallax in experimental animals, 
but not of high potency. It is stated that the serimi of men infected 
with the organism shows specific agglutinins after a period of two or 
more weeks. 
Bacteriological Diagnosis.— The morphology is somewhat distinctive: 
Small, encapsulated bacilli with rounded ends occurring singly, quite 
motile, and stained by Gram's method. 
Cultural.— The cultural reactions are not distinctive. The action 
upon milk is less vigorous than the other gas gangrene bacilli. The 
fermentation of glucose and saccharose is less vigorous than that of 
Vibrion septicjue and B. welchii. The action upon lactose is distinctly 
slower than that of other sugars. Starch fermentation is of importance, 
and should not be overlooked. The organism is not proteolytic. 
Serological.— An occasional patient exhibits specific agglutinins for 
B. fallax. The organism may be clumped by a specific agglutinating 
serum. 
BACILLUS TERTroS. 
Bacillus tertius is an anaerobic bacillus which was frequently met 
with by Henry^ in his study of the anaerobic microbes of infected 
wounds of warfare. It has previously been identified by Miss Robert- 
son- as Bacillus IX of v. Hibler.^ Weinberg and Seguin'* believe it to 
be identical with Bacillus III of Rodella.^ 
1 Jour. Pathol, and Bacteriol., 1917, 21, 344. '- Ibid., 1915-1916, 20, 327. 
3 Untersuch. u. d. path. Anaeroben, etc, Jena, 1908. 
* La Gangrene Gazeuse, Paris, 1917, s Ztschr. f. Hyg., 1902, 39,201. 
