146 A MANUAL OF BACTERIOLOGY 



alcohol and ether. It is said that ether dissolves out 

 a red-violet pigment, and alcohol a deep blue one. 



Bacterium brunneum. ' Motile rods, producing a 

 brown colour. They were observed on a rotting 

 infusion of maize.' 



Proteus vulgaris. This bacterium is found in 

 abscesses, putrefying organic matter, meconium- 

 fseces, and in water. The rods are from 1'25 to 3*75 

 /j, in length, and about 0'6 //, in breadth. The 

 threads or chains are usually twisted and convo- 

 luted, and, according to Hauser, 1 involution forms 

 are found spherical bodies about 1*6 //, in diameter. 

 This microbe grows rapidly in nutrient gelatine, 

 causing liquefaction of the gelatine. In test-tube 

 cultivations, the fluid gelatine, which is at first 

 turbid, becomes subsequently more or less clear in 

 the middle, with a' deposit of flocculi at the bottom, 

 and a slight turbidity at the top. Growing on 

 gelatine plates, this microbe rapidly forms greyish 

 masses, which consist of motile and swarming colo- 

 nies. After forty-eight hours' growth a foul odour 

 and an alkaline reaction are developed. This 

 microbe is pathogenic, and produces abscesses or 

 death according to ,the dose or quantity of the 

 microbian culture injected into the animal ; with 

 rabbits and mice inoculation does not cause any 

 effect, but the injection of quantities varying from 

 ^ to T 3 o cc. causes death. On this point Watson 

 Cheyne 2 states ' that T V cc. injected into the mus- 

 cular tissue was a fatal dose, indeed V cc. almost 



1 Ueber Faulniss-Bacterien, 1885. 



2 British Medical Journal, July 31, 1886. 



