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CERTAIN GENERA OF THE CLOSTRIDIACEAE 



STUDIES IN PATHOGENIC ANAEROBES. V 

 HILDA HEMPL HELLER 



From the George William,^ Hooper Foundation for Medical Research, University of 

 California Medical School, San Francisco 



Received for publication March 1, 1921 



In a previous paper a classification was suggested for the 

 group of anaerobic rods which include, roughly, the anaerobic 

 members of the genus Bacillus of former workers. A family 

 was proposed for these organisms, with the name Clostridiaceae ,^ 

 and it was divided into two subfamihes, the Putrificoideae^ or 

 , proteolytic anaerobes, and the Clostridioideae^ or non-proteoly- 

 tic anaerobes. Certain genera for these groups are proposed in 

 the present communication. These in some cases unite various 

 described species, while in other cases the genera themselves 

 correspond to the former idea of species. 



A key to the genera is also given, which is based on the action 

 of the anaerobes on meat medium and on their general cultural 

 behavior and morphology. Possibly the main lines for tribal 

 organization will to some extent follow this key, but it pretends 

 to be no more than an artificial arrangement. It is in no way 

 complete and cannot be implicitly relied upon for purposes of 

 classification. It is meant more as an index to the forms whose 

 descriptions are sufficiently clear to warrant assigning them de- 

 finite positions. The kej'^ will serve, for a time, as a nest of 

 pigeonholes in which to place new species until material is suffi- 

 cient for a complete reorganization, but workers should not try 

 to place all newly discovered organisms in these genera. 



The conservative worker, famiUar with aerobic pathogens, 

 who enters the anaerobic field, is all too prone to wish to ' ' identify" 



' For definition see Jour. Bact., 6, 536. 

 ' For definition see Jour. Bact., 6, 550. 



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JOURNAL OF BACTERIOLOQT, VOL. VII, NO. 1 



