CLASSIFICATION OF ANAEROBIC BACTERIA 523 



groups thus studied we shall be enabled so to orient our classi- 

 fication of the whole anaerobic group that some conception of 

 its size and general relationships will be presented for the use of 

 future investigators. 



The uncertainties prevaihng in the classification of the an- 

 aerobes, apparent to anyone who has tried to identify an isolated 

 anaerobic strain, become more glaring as one proceeds to study 

 several strains that were handed to him under the same name, 

 but which display great differences in their behavior. Later, 

 on continuous study of anaerobes of various types, and of the 

 literature of anaerobic infections, the worker comes to the reali- 

 zation that identifications by means of descriptions found in the 

 existing literature can at best be only tentative and approxi- 

 mate, and that the majority of those type strains on which were 

 based the descriptions to which we are compelled to refer for 

 priority are now lost or badly contaminated. Thus a large 

 number of the older descriptions are potentially invahdated, 

 or orphaned, so to speak, and cannot, today, be used for any 

 definite systematic purpose, and the names proposed in those 

 descriptions are now nomina niida. This situation must be 

 dehberately faced. What we need is an elastic, adaptable system 

 of classification in which the old descriptions can find a place 

 as well as the new: a system consistent, also, with the Rules of 

 Botanical Nomenclature, whose adoption has been proposed by 

 the Committee of the Society of American Bacteriologists. 



FORMER CLASSIFICATIONS 



It is necessary to consider what have been the methods of 

 classifying our group that have been proposed by other workers. 



Zopf defined the genus Bacillus as including: "Cocci and rods 

 with spores" and the genus Clostridium as: "Like Bacillus but 

 spores in spindle-shaped elements." 



Kruse (1896, pp. 67 and 185) included in his family of BaaZ- 

 laceae three groups which comprise the anaerobes. They are: 



6. The malignant oedema group: large spore-bearing anaerobic 

 bacilli. Saprophytic or parasitic. Colonies on agar usually stellate. 



JO0RNAL OF BACTERIOLOOT, VOL. VI, NO. 6 



