40 CLINICAL BACTERIOLOGY 



Bacillus Coli Communis. 



Biological Characters. — 1. In broth it forms a diffused 

 cloudiness of the medium. 



2. On gelatin plates it forms iridescent colonies. Gelatin 

 does not liquefy. 



3. In gelatin stab culture it grows in the form of a nail. 



4. On agar and blood serum a thick layer forms, moist 

 and slimy. 



5. On potato the growth at 20° C. is brown and slimy. 



6. In litmus milk it forms acid, gas, and clots. 

 Staining. — Original carbol - methylene blue ; culture 



Gram's method, and weak carbol - fuchsin as a contrast 

 stain. 



Microscopical Appearances. — Short motile rods, mosthy in 

 pairs, sometimes in threads. 



Both aerobic and anaerobic. Grows at room or in- 

 cubator temperature. 



Bacillus Anthracis Symptomatica. 



Biological Characters. — 1. On gelatin plates in an 

 atmosphere of hydrogen a radiating dull area forms, the 

 gelatin liquefies, and a dark lobulated centre develops. 



2. In deep stab glucose gelatin gas forms. 



3. In glucose agar it forms a dense grey-coloured growth, 

 and gives off a pungent-smelling gas. 



Staining. — Carbol-methylene blue, but not ordinarily by 

 Gram's method. 



Microscopical Appearances. — The bacillus is motile with 

 rounded ends, usually single, sometimes forming threads. 

 Spores form at the ends or in the middle. 



Strictly anaerobic, growing at room or incubator tem- 

 perature. 



Bacillus Bronchosept icus [Ferry). 



Biological Characters. — 1. In broth cloudiness take 

 place after twenty-four hours. 



