DESCRIPTION OF SPECIES 



4Q7 



gas formation. Able partly to 

 liquefy (peptonise) coag^ated 

 casein. 



Freudenreich obtained Kephyr in 

 sterile milk most often by mixing 

 the Kephyr yeast with 2 streptococci 

 isolated from Kephyr and the B. 

 caucasium. 



Non-pathogenic. 



BACIIiliUS CIRCUIiANS, No. 2 



(Jordan). 



Source and habitat — From milk by 

 Conn. 



Morphology — 6 m broad by 1-5 \x long ; 

 long chains are produced in bouil- 

 lon. 



Staining reaction — Ordinary aniline 

 dyes. 



Motility — Motile. 



Spore formation — Found in most 

 media by Jordan, not by Conn. 



Biology : cultural characters {includ- 

 ing biochemical features). 



Gelatine plates and tubes — A 

 granular colony sinking into a dry 

 pit, the pit liquefies and the bacilli 

 can be seen circulating in the 

 liquid. In stab-cultures a deep 

 narrow funnel is produced with a 

 white sediment. 



Agar plates and tubes — An 

 abundant yellowish growth, which 

 is not characteristic. 



Potato — A thin, watery, trans- 

 parent growth. 



Milk — Is not curdled but digests 

 into a weakly alkaline liquid which 

 is cloudy and gives off unpleasant 

 odours. Gives butter a good 

 flavour, the putrefactive odour 

 present in milk and cream is not 

 present in butter. 

 Aerobic. 

 Non-pathogenic. 



BACILLUS CITRBUS ACIDI (Conn), 

 Source and habitat — Milk. 

 Morphology — Rod ; -8 /* long by -4 /t 

 broad ; singly. No chains or groups. 



Staining reaction — Ordinary aniline 



stains. 

 Biology: cultural characters {includ- 

 ing biochemical features). 



Bouillon — A slight scum which 

 eventually sinks as abundant sedi- 

 ment. 



Gelatine plates and tubes — Large 

 white opaque colony turning yellow. 

 In stab-cultures a good needle 

 growth with spreading surface, 

 depressed centre, raised edge, 

 becoming lemon yellow. 



Agar plates and tubes — An abun- 

 dant spreading growth, lemon 

 yellow in colour. 



Potato — A thick white, slightly 

 transparent growth ; centre becomes 

 yellow and eventually whole growth. 



Milk — Curdled at ordinary tem- 

 peratures in 6 to 9 days with clear 

 hard curd ; acid reaction. Same 

 change occurs in cream with gas 

 production ; produces a good 

 butter. 



Aerobic. 



Non-pathogenic. 



BACILLUS CITRE5US ARBOR- 

 BSCENS (Conn). 



Source and habitat — Milk. 



Morphology — A rod 4 m long by -8 m 

 broad. Two or three may adhere 

 together, but no long chains. 



Staining reaction — Ordinary- aniline 

 stains. 



A capsule which does not stain. 



Biology : cultural characters {includ- 

 ing biocheynical features). 



Gelatine platesand tubes — Widely 

 spread colonies with fine radiating 

 rods growing from centre outward 

 over medium. These fibres have 

 frequent nodules. Looks like a 

 mould to the naked eye. In stab- 

 cultures a slight needle growth, 

 but a thick groimd-glass surface 

 gfTowth occurs. 



