344 APPLIED BACrERlOLOGY 



branches. In the depth characteristic zoogloea forms are 

 met with. 



Gelatine Tubes. — The gelatine is rapidly liquefied, when 

 the whole of the contents are liquid ; a whitish-gray cloud 

 is visible at the surface, while at the bottom collects an 

 abundant thick crumbly deposit. 



Agar-Agar. — A thin- spreading, moist, shining, grayish- 

 white expansion is formed. 



Potatoes. — A dirty- white smeary growth is formed. 



Proteus Mirabilis. — This organism is found in water, 

 putrefying animal substances, etc. It occurs in rods of 

 different lengths up to 2 or 4 /a long by 0'6 /x broad. It is 

 very motile, and readily gives rise to involution forms. 

 Cultural characters : 



Gelatine Plates. — The colonies form circular white ex- 

 pansions, which, under low powers, appear brownish and 

 finely granular. Liquefaction is less rapid than in the 

 case of the Proteus vulgaris. 



Gelatine Tubes.- — Forms a whitish expansion, surrounded 

 by a liquid circular zone, filled with moving bacilli. At 

 the end of forty-eight hours, a moist, thick, shining pellicle 

 is formed. The whole contents of the tube are liquefied in 

 two or three days. 



Agar-Agar. — A moist, shining, dirty-white expansion is 

 formed. 



Both the above protei are pathogenic to rabbits and 

 guinea-pigs. 



Bacillus Ramosus {Wurzel bacillus). — This organism is 

 found in the soil and water. Frequently found by Frank- 

 land in the water of the Thames and the Lea. It much 

 resembles the B. subtilis. It strongly reduces nitrates to 

 nitrites. The bacilli are about 7 fi long and 1"7 fi broad, 

 the ends being rounded. It occurs in long threads and has 

 resistant spores. Cultural characters : 



