546 THE ANAEROBIC BACTERIA 
Cultural.— The dual ability of inducing fermentation in glucose media 
with the formation of a mucinous deposit, and the strong putrefactive 
activity in non-saccharine media is a marked feature of this organism. 
The absence of pathogenicity for small animals is another characteristic 
which is of assistance in arriving at a diagnosis. 
BACILLUS (EDEMATIENS. 
Bacillus oedematiens was described by Weinberg and Seguin^ as 
one of the more important incitants of gas gangrene. The organism 
appears to be quite similar to Novy's^ Bacillus of IVIalignant Edema. 
Weinberg and Seguin^ state that the organism described by Costa and 
Troisier* as the "B. neigeux," and the gas edema bacillus of Aschoff' 
exhibit many characters in common with B. oedematiens. 
Morphology.— The organism is a rather long, thick rod with rounded 
ends measuring from 0.8 to 1 micron in diameter, and from 4 to 8 
microns long. Exceptionally, the organism may be as short as 2.5 
microns, or as long as 10 microns. The ends of the shorter forms are 
frequently more square cut, and therefore like B. welchii (which 
the organism resembles in appearance, except for its greater length), 
while the longer rods have very distinctly rounded ends. The long 
axis of the longer forms is also frequently curved so that single cells 
are somewhat C shaped, and pairs of organisms may resemble some- 
what a letter S. B. oedematiens is found more commonly in pairs 
but chains of greater or lesser length are occasionally met with in fluid 
cultures. Chains are rarely, if ever, found in pathological material, 
however. Capsules have not been described. 
Motility is denied by Weinberg and Seguin, but several authentic 
strains have shown motility in young actively growing cultures, care- 
fully shielded from the air.*^ Weinberg and Seguin state, however, that 
the organism possesses a dozen or more peritrichic flagella. 
Spores.— B. oedematiens sporulates readily, even in carbohydrate 
containing media. The spores are greater in diameter than the parent 
cell, oval, (0.8 to 1.2 x 1.5 to 2 microns) and when observed in the rod 
present an appearance that has been likened to that of a tennis racquet. 
Staining.— Organisms from tissues and from >oung vigorous cultures 
are strongly Gram-positive, but within a very few days, as soon as 
sporulation is well established as a rule, the vegetative cells not only 
fail to retain the Gram stain, they also lose to a considerable degree 
their ability to color uniformly with the ordinary anilin dyes. 
Isolation and Culture.— The organism grows in pure culture only in 
media carefully freed from oxygen ; it is one of the most exacting of the 
1 Compt. rend. Soc. de biol., 1915, 78, 274, 507. 
= Ztschr. f. Hyg., 1894, 17, 209. 
■■* La Gangrene Gazeuse, Paris, 1917. 
" Compt. rend. Soc. de biol., 1915, 78, 352. 
5 Veroffentl. a. d. Geb. d. Mil. Sanitlitswesens, 1918, 68, 1. 
6 Kendall, Dav and Walker: Jour. Inf. Dis., 1922, 30, No. 2 
