314 BACTERIOLOGY 



Gelatin stab. Liquefaction infundibuliform, an air space above ; sediment 



whitish-pinkish. 

 Agar slant. Growth grayish, glistening, limited, translucent, brownish gray. 

 Bouillon. Turbid, flocculi in suspension, a slight pellicle, and a slight greenish 



tint to the medium. 

 Potato. Growth thin, viscid, moist, glistening, brownish. 

 Litmus milk. Coagulated, decolorized, alkaline. Indol not produced. No 



growth at 35-36. 



Habitat. Water. 



1 6. Ps. delabens (Wright) 



B. delabens Wright : I.e., 456. 



Morphology. Bacilli small, short, and long forms. 



Gelatin colonies. Deep : round irregular, slightly granular, brownish yel- 

 low. Surface : thin, translucent, glistening, wavy irregular, centre 

 grayish ; microscopically, thin, translucent, marmorated, brownish centre ; 

 later the growth sinks in the slowly liquefied gelatin. 



Gelatin slant. Growth a gray white stripe which sinks into the gelatin. 



Gelatin slab. In depth, growth beaded, brownish gray; on the surface, 

 growth thin, white, irregular, which sinks slowly into the liquefied 

 gelatin. 



Agar slant. Growth whitish, translucent, glistening, slightly spreading ; the 

 agar becomes greenish. 



Bouillon. Turbid ; a slight pellicle, and a slight greenish tint. 



Potato. Growth brownish, viscid, thick, spreading. 



Litmus milk. Decolorized, not coagulated, alkaline ; a tough membrane. 

 Indol slight. Nitrates not reduced. No growth at 36 . 



Habitat. Water. 



CLASS III. WITHOUT ENDOSPORES. AEROBIC AND FACULTATIVE 

 ANAEROBIC. CHROMOGENIC, PIGMENT ON GELATIN OR AGAR. 



I. Pigment yellowish. 



A. Gelatin liquefied ; no gas in glucose bouillon. 



1. Milk coagulated. 



a. Grow well at 35-36 C. 



17. Ps. pullulan s (Wright). 



b. Do not grow at 35-36 C. 



18. Ps. annulata (Wright). 



2. Milk not coagulated. 



19. Ps. ochracea (Zimmerman). 



20. Ps. campestris (Pammel) Smith. 



