528 C. A. LAUBACH, J. L. RICE AND W. W. FORD 



AEROBIC SPORE-BEARING NON-PATHOGENIC BACTERIA 



Group I. Suhtilis group 



Small homogeneous sluggishly motile organisms measuring 

 0.375 by 1.5 to 2.5 microns. No threads on glucose agar. Cen- 

 tral or ex-centric spores, oval, measuring 0.5 by 0.75 to 0.875 

 microns, often retaining terminal tags of protoplasm. Growth 

 on soh'd media hard and penetrating, with tenacious scums on 

 fluid media. 

 Represented by 



Bacillus suhtilis Cohn. 

 Bacillus suhtilis-viscosus Chester. 

 (Characterized by viscosity.) 



Group II. Mesentericus group 



Small homogeneous actively-motile organisms measuring 0.5 

 by 2 to 4 microns. Often produce long threads on glucose agar. 

 Spores measure 0.5 by 1 to 1.125 microns, oval, retaining termi- 

 nal tags of protoplasm. Growth on hard media as soft pulta- 

 ceous mass with tendency to wrinkle, on fluid media as friable 

 easily-broken scums. 

 Represented by 



Bacillus vulgatus (Fltigge) Trevisan. 



{Bacillus mesentericus vulgatus Fltigge.) 

 Bacillus mesentericus (Fltigge) Migula. 

 (Bacillus mesentericus fuscus Fltigge.) 

 Bacillus aterrimus Lehmann & Neumann. 



(Bacillus mesentericus niger Lunt.) 

 Bacillus glohigii Migula. 



(Bacillus mesentericus ruber Globig.) 

 Bacillus niger Migula. 



(Bacillus lactis niger Gorini.) 

 Bacillus mesentericus var. fiavus. 

 Bacillus panis Migula. 



(Bacillus mesentericus panis viscosi I Vogel.) 

 (Motility lost by capsule formation.) 



