68 MANUAL OF DETERMIXATIVE BACTERIOLOGY 



oc. Gram-negative rods. When motile, from four to many peri- 

 trichous flagella. 



d. Grow well on ordinary media containing peptone. Aerobic 

 to facultative anaerobic. 



e. Gram-negative, straight rods which ferment sugars 

 with the formation of organic acids, 

 f. Produce little or no acid in litmus milk. May or 

 may not reduce nitrates. Many yellow chromo- 

 gens. Borderline between this and following 

 family indistinct. Some species anaerobic. 

 Family IX. Achromobacteriaceae, p. 412. 

 ff. Produce CO2 and frequently visible gas (CO2 + 

 Ho) from glucose. Reduce nitrates. Usually 

 from the alimentary, respiratory or urinary tract 

 of vertebrates, though some are free-living or even 

 plant parasites. 



Family X. Enlerobacteriaceae, p. 443. 

 dd. Small Gram-negative rods. Obligate parasites which 

 usually require body fluids for growth. Do not grow well 

 on ordinary media. Some are anaerobic. 



Family XI. Parvobacteriaceae, p. 545. 

 ccc. Rods of varied types not included in above families. 

 Aerobic to facultative anaerobic. 



Family XII. Bacteriaceae, p. 596. 

 II. Form endospores. Large rods, sometimes in chains. Aerobic to anaerobic. 



Family XIII. Bacillaceae, p. 704. 



