PATHOGENIC BACTERIA. 



113 



crococcus of sputum septicaemia ; Micrococcus Pasteuri ; Diplo- 

 coccus lanceolatus. 



Origin. A, Fraukel found it in the sputum of pneumonic 

 patients, thinking it at first to be the micrococcus of sputum 

 septicaemia ; later he believed it to be the cause of pneumonia. 



Form. Oval cocci they were at first called, but they are now 

 known to be rod-shaped, being somewhat longer than broad ; 

 varying, however, much in size and shape. Usually found in 

 pairs, sometimes in filaments of three and four elements. In 

 the material from the body a capsule surrounds each rod. In 

 the artificial cultures this is not found. 



FIG. 59. 



Bacillus of Pneumonia in Saliva. (After Biondl.) 



Properties. They are without self-movement ; do not liquefy 

 gelatine. 



Growth. Grow only at high temperature, 35 C. ; are facul- 

 tative anserobic. The culture media must be slightly alkaline ; 

 the growth is slow. 



Colonies on Gelatine Plates. Since the temperature must be 

 somewhat elevated, the gelatine media need to be thicker than 

 usual (15 per cent, gelatine), in order to keep it solid, and a 

 temperature of 24 C. used. Little round white colonies, some- 

 what granular in the centre, growing very slowly. 

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