AEROBIC SPORE-BEARING NON-PATHOGENIC BACTERIA 529 



Group III. Cohaerens-simplex group 



Motile organisms somewhat larger than either Bacillus sub- 

 tilis or Bacillus mesentericus, measuring 0.375 to 0.75 by 0.75 to 

 3 microns. Thicker and longer forms on glucose agar. Invo- 

 lution and shadow forms common and appear early. Spores 

 cylindrical, measuring 0.5625 to 0.75 by 1 to 1.5 microns. 

 Growth as a soft mass on hard media, as turbidity with little 

 or no scum on fluids. 

 Represented by 



Bacillus cohaerens Gottheil. 



Bacillus simplex Gottheil. 



Bacillus agri nov. sp. 



Group IV. Mycoides group 



Large organisms with square ends growing in long chains. 

 Single cells measure 0.5 by 3 to 6 microns. On glucose agar 

 organisms are thicker and longer and made up of globular bod- 

 ies. Tendency for organisms to grow in curves or spirals. 

 Spores central or ex-centric, round or oval to cylindrical, meas- 

 uring 0.75 to 1 by 1 to 2 microns. Spores vary greatly in size 

 and often appear in chains. Growth on hard media dry and 

 penetrating, on fluid media as firm tenacious scum. 

 Represented by 



Bacillus mycoides Fliigge. 

 Bacillus prausniizii Trevisan. 



{Bacillus ramosus liquefaciens Prausnitz.) 

 Bacillus adhaerens nov. sp. 

 (No motility.) 



Group V. Cereus group 



Large motile organisms with round ends measuring 0.75 by 

 2.25 to 4 microns. Tend to grow in short chains. Thicker and 

 longer on glucose agar where protoplasm is converted into glob- 

 ular bodies. Central or excentric spores, cylindrical, measur- 

 ing 0.5 to 0.75 by 1.125 to 1.5 microns. Spores retain proto- 



