400 MICRO-ORGANISMS IN WATER 



VIBEIO BiaiOLINENSIS 



LIQUEFIES GELATINE 



Authority. — Neisser, 'UebereinenneuenWasser-Vibrio,derdie Nitrosoindol- 

 reaction liefert,' Archivf. Hygiene, 1893, p. 194. 



Where Found. — In filtered river Spree water. 



Microscopic Appearance.— Usually somewhat smaller than the cholera 

 bacillus ; otherwise undistinguishable. Very motile ; one long and much twisted 

 ciUum is attached to one end of the rod. No spore formation observed. Is 

 discoloured by Gram's method. 



Cultures. — 



Gelatine Plates. — Liquefies the gelatine much more slowly than the cholera 

 bacillus ; is often hardly visible on the plate, even after forty-eight hours. Under 

 the microscope at the end of twenty-four hours the depth colonies are small, 

 circular and smooth-rimmed, the contents are very slightly and finely granulated, 

 they are colourless and transparent. The surface colonies form small trans- 

 parent skin-like expansions, with a central circular disc. No depression is formed 

 in the gelatine, and the edge of the colony always remains sharply defined. 



Gelatine Tubes. — In gelatine tubes it is only distinguished from the 

 cholera bacillus by its markedly slower growth. 



Agab-agar and Glycehine-agab. — Resembles the cholera bacillus* 



Potatoes. — On ordinary potatoes, as well as on those treated with soda, 

 vinegar, and salt respectively, it resembles the cholera bacillus. 



Broth. — Renders strongly alkaline broth more xapidly and decidedly turbid 

 at 20° to 22° C. and at 37° C. than the cholera bacillus ; otherwise resembles the 

 latter. Grows very luxuriantly and much more so than the cholera bacillus in. 

 pancreas broth. 



Sterile Water. — At 37° C, after six days no visible growth, but when 

 sterile 1 per cent, pepton-water was added to these tubes, turbidity began 

 forty-eight hours later ; the cholera bacillus tube, however, remained clear, no 

 growth having taken place. 



Sterile Mllk. — No coagulation, and forms no acid ; therefore resembles the 

 cholera bacillus. 



Remarks, — It will not grow at 10^ C, and is destroyed when kept at 60° C. for 

 five minutes. Gives the * cholera-red * or nitrosoindol reaction. Is pathogenic to 

 guinea-pigs, but not to mice, rabbits, or pigeons. 



Note.— Sanarelli (' Les Vibrions des Eaux et I'Etiologie du ChoMra,* Annales de 

 VInstitut Pasteur, vol. vii., 1893, p. 693) isolated no less than thi;cty-two different 

 vibrios from the river Seine, drain-water, sewage-effluent, and pond- water, four of which 

 gave the ' cholera-red ' or nitrosoindol reaction and were pathogenic to guinea-pigs. 

 Sanarelli is of opinion that there may be numerous vibrios capable of exciting cholera, 

 and that the idea of its propagation being due to one particular- variety is untenable. 

 (See pp. 279 and 283.) 



