114 MORPHOLOGY AND CULTURE OF MICROORGANISMS 



THE FAMILIES AND GENERA OF THE BACTERIA 



Report of the Committee of the Society of American Bacteriologists. C.-E. A. 



Winslow ct al. (Artificial key) 



ORDERS OF THE SCHIZOMYCETES 



Cells united during the vegetative stage into a 



pseudoplasmodium MYXOBACTERIALES 



Cells not forming a pseudoplasmodium 



Cells free or united in elongated filaments, often 

 with a well denned sheath. Conidia fre- 

 quently formed. Free sulphur, iron or 

 bacteriopurpurin often present. 

 Cells typically containing granules of sulphur or 



bacteriopurpurin or both THIOBACTERIALES 



Suilphur and bacteriopurpurin absent; iron often 



present CHLAMYDOBACTERIALES 



Cells ne\~er in sheathed filaments. Conidia only 

 in mycelial Mycobacteriaceae. Flagella often 

 present. Free iron, sulphur, or bactiopurpurin 

 never present .EUBACTERIALES 



FAMILIES OF THE EUBACTERIALES 



Cells spiral with polar flagella IV. SPIRILLACE^E 



Not as above 



Cells spherical; rarely, if ever, motile; spores 

 never produced; never securing growth energy 



from nitrogen or ammonia V. COCCACEJi 



Not as above 



Cells short rod-shaped with a single, rarely two, 

 polar flagellum; usually forming green or 



yellow pigment III. PSEUDOMONADACE^ 



Not wholly as above 



Spores formed VIII. BACILLACE^ 



Spores never formed 



Metabolism simple, securing growth energy 

 from carbon, hydrogen, or their simple 



compounds; flagella, if present, polar I. NITROBACTERIACE^ 



Metabolism complex, dependent upon more 

 complex carbohydrate and protein sub- 

 stances; flagella, if present, peritrichic. 

 Cells clubbed, fusiform, filamentous, 

 branching or mycelial; those not distinctly 

 so are either acid-fast or show barred 



irregular staining IT. MYCOBACTERIACE^ 



Not as above 



Gram positive; non-motile VI. LACTOBACILLACE^ 



Gram negative; often motile VI. BACTERIACE,E 



