762 PATHOGENIC MICROORGANISMS 



B. sporogencs was definitely described by Metchnikoft' 29 in 1908. 

 Whether B. sporogenes is identical or not with Koch's bacillus of 

 malignant edema, will probably never be definitely settled. It is 

 considered identical by many workers, although this is emphatically 

 denied by others. B. sporogenes is a Gram-positive, anaerobic 

 bacillus, actively motile, forming oval subterminal spores readily 

 in all media and in the animal body. It is intensely proteolytic, 

 liquefying gelatin and coagulated serum, and digesting and blacken- 

 ing meat. Most strains of B. sporogenes are not hemolytic. Occa- 

 sionally a feebly hemolytic strain has been isolated. It does not 

 produce a soluble toxin and is not pathogenic for laboratory animals 

 unless injected in large quantities. 



B. Histolyticus. This organism was discovered by Weinberg 

 and Seguin and isolated by them from eight wound cultures. Like 

 B. sporogenes, it is intensely proteolytic and is of interest chiefly 

 because of the striking lesion it produces in the animal body. It 

 is a Gram-positive anaerobic, motile bacillus with rounded ends. 

 Sporulation takes place in all media, different strains varying in 

 the time required for spore formation. The spores are large and 

 oval, and occupy a terminal position. No gas is formed in cultures 

 of B. histolyticus and no putrid odor develops. Gelatin and coagu- 

 lated serum are liquefied. It does not produce a soluble toxin. It 

 is not hemolytic. The injection of large doses, 2 to 3 c.c. intra- 

 muscularly into guinea pigs, of the whole culture digests the tissues 

 so rapidly that at the end of twelve to twenty-four hours, the bone 

 may be exposed. The picture is striking, one of the characteristics 

 of B. histolytic infection being that in spite of a tremendous local 

 lesion, the animal appears well. 



B. putrificus. B. putrificus was occasionally found in putrid 

 wounds. It was first discovered in 1884 by Bienstock and is char- 

 acterized by a terminal oval spore. Bienstock isolated B. putrificus 

 from the intestine of a cadaver. It is a Gram-positive anaerobe, motile, 

 forming spores in all media. It is actively proteolytic, producing 

 a foul odor. No pathogenic strains have been isolated. It has been 

 studied by Tissier and Martally who found it in putrid meat, Klein 

 worked with a similar organism which he called B. sporogenes 

 cadaveris. Hibler considers B. putrificus and B. sporogenes cada- 

 veris the same. 



29 Metchnikoff, Ann. de 1'Inst. Past,, 22, 1908, 419. 



