NON-SPORING BACILLI 241 



Characteristics. A short plump bacillus with rounded 

 ends, but showing some very long forms (0-6 to 5 micra long 

 by 0-5 to 1-5 micron). The short thick forms are mostly 

 found in animal tissues, and at times are almost coccoid. 

 In sputum it shows a capsule, and in other preparations 

 from the body. It occurs in pairs, and hence has been 

 called a diplobacillus. It may also form short chains. 

 It is non-motile, non-flagellar, non-sporing, non-gelatin- 

 liquefying, and non-Gram (i.e., Gram-negative). 



Cultures. It grows readily on ordinary media and in 

 gelatin at room temperature. It grows well on acid or 

 alkaline media, is aerobic, and facultatively anaerobic. 



In broth : rapid abundant growth with a pellicle, general 

 clouding, and later a stringy sediment. 



On agar : sticky mucus-like colonies of a greyish-white 

 colour. 



In gelatin stab : a white line of growth at first, but with 

 increasing growth at surface a " nail-head " appearance 

 is produced. This was at one time thought to be peculiar 

 to Friedlaender's bacillus. 



On potato : abundant, somewhat brownish growth. 



In peptone water : no indol formation. 



In milk : abundant growth with capsule formation. 

 Acid and clot are slowly formed. 



Pathogenicity. For man : pneumonia of a severe and 

 fatal type ; ulcerative stomatitis and nasal catarrh ; 

 acute tonsillitis ; in antral suppurations and in foetid 

 coryza ; and, on rare occasions, in septicaemia. 



For animals : a mouse injected at the root of the tail 

 dies in two days of septicaemia. It is also pathogenic for 

 guinea-pigs ; less so for rabbits. 



DISTINCTION FROM THE PNEUMOCOCCUS. 



Allied bacilli are : B. ozaenae, found in foetid nasal 

 catarrh, which is scarcely separable from B. mucosus, 



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