CLASSIFICATION OF BACTERIA 39 



2. Cells motile 



A, Same as Micrococcus, but with flagella Phnococcus 



B, Samo as Sarcina, but flagella Planosarcina 



Family II. Bacteriaceae. Cells cylindrical in shape, not bent 



1. Cells non-motile Bacterium 



2. Cells motile Pseudomonas 



3. Cells with peritrichous flagella Bacillus 



Family III. Spirillaceae, Cells elongated and bent, usually spirals or seg- 

 ments of spirals 



1, Cells non-motile Spirosoma 



2. Cells motile 



A, Cells, short, comma-shaped, one to three polar flagella 



Microspira 



B, Cells longer, with tufts of polar flagella Spirillum 



C, Cells very long and slender, flexible, flagella (if present) demon- 



strated only with difliculty Spirochaeta 



Suborder II. Trichobacteria» 



Family Chlamydobacteriaceae. Cells cylindrical, united in threads or fila- 

 ments surrounded by a sheath 



A* Filaments unbranched Leptothrix 



B. Filaments showing false branching n. . Cladothrix 



C, Filaments showing true branching 



(1) Spores produced Nocardia 



(2) No spores observed Actinomyces 



This classification is especially unsatisfactory to the student of 

 soil bacteriology as there is no appropriate place within it for 

 many of the soil bacteria. Moreover, the small number of genera 

 makes it necessary to class together organisms which are similar 

 in morphology but which are far different in action. This is 

 overcome in a new classification suggested by a committee of the 

 Society of American Bacteriologists.* 



Classification o£ Society of American Bacteriologists. — 



The outline of this classification, as condensed by Macy, is given 

 on the following page, 



* Those desiring a more complete statement of this classification will find it 

 complete in Journal of Bacteriology, Vol. 5, No. $ (May, 1920), pp. 191-215, 

 or in "General Systematic Bacteriology" by Buchanan (1924.), published by Wil- 

 liams & Wilkins, Baltimore. 



