150 BACTERIOLOGICAL EXAMINATION OF WATER. 



Gelatine-shake Culture. There is no gas formation. 



Broth. It grows rapidly at 37 C., producing a flocculent 

 growth. On the surface a skin is formed, which sinks on 

 shaking the tube. 



Indol There is no formation of indol in broth cultures. 



Litmus-milk. A gelatinous clot is formed and the medium 

 becomes faintly acid. 



Potato. A dirty, faint, yellowish-grey coloured growth. 



Nitrate-broth. Great reduction of nitrates in one night 

 at 37 C. 



Microscopical Characters, $c. A non-motile, very large 

 bacillus, which forms long chains. The cultures resist heating 

 to 80 C., but a satisfactory double-stained spore preparation 

 has not been obtained. It grows well at 37 C. and at the 

 room temperature. 



Bacillus Capillareus. 



Isolated from crude sewage and effluents from coke-beds. 



Gelatine-plate Cultures. The colonies in the depth have a 

 characteristic fluffy appearance, and when they reach the 

 surface quickly liquefy the gelatine. The growth is 

 filamentous in the depth, and on the surface from the spreading 

 edge of the colonies delicate film-like processes are given off, 

 which extend over the surface of the medium to form irregular 

 patterns. Later, the final details are lost owing to the rapid 

 liquefaction of the gelatine, the colonies appearing as large, 

 more or less circular, areas of liquefaction with greyish- white 

 contents. 



Agar-streak. In twenty-four hours an opaque-white growth 

 of limited extent appears, which along the spreading edge is 

 slightly transparent and granular-looking. 



Gelatine-streak. A longitudinal furrow appears due to the 

 liquefaction of the gelatine; from the edge of the furrow 

 delicate processes may be seen, extending in irregular fashion 

 over the solid surface of the gelatine. 



Gelatine-stab. Liquefaction takes place in funnel form, and 

 extends down the stab to an extent varying in different cultures. 

 Along the line of inoculation feathery processes are given off, 

 which extend into the solid gelatine for a short distance. The 



