442 A MANUAL OF BACTERIOLOGY 



Group 3. The third group is formed by vibrios which 

 are not agglutinated by immune serum, nor give the 

 saturation or Pfeiffer's reaction, but fix the cholera-immune 

 body. These vibrios also hsemolyse, but feebly and late, 

 often only after thirty-six to forty-eight hours. 



Group 4. The last group is formed by strongly hsemo- 

 lytic vibrios not reacting at all to cholera-immune serum. 



Buffer concludes that the El Tor vibrios are not genuine 

 cholera vibrios. He says : " The only possible classifica- 

 tion is to group together all the vibrios reacting in the 

 same way to all tests, separating them from those which, 

 under the same conditions, behave in a different way. If 

 this method be applied to the vibrios found at El Tor, 

 there is no difficulty in distinguishing them from the true 

 cholera vibrios, in spite of several of the reactions of both 

 being similar. And it follows also that the agglutination, 

 saturation and Pfeiffer's tests are not in themselves of 

 absolute diagnostic value for cholera vibrios." 



Neufield and Haendel, 1 however, after a re- examination 

 of some of these vibrios, consider that they are true cholera 

 vibrios. The matter therefore remains undecided. 



Klein found that the cholera vibrio kept in sea- water 

 showed marked variation from the original strain. In 

 the East many cases of cholera are mixed " vibrionic " 

 infections ; the stools may contain several varieties of 

 vibrios, some agglutinating with cholera serum, others 

 not ; some monociliate, others multiciliate. 



It may be that, like the B. dysenteries, the cholera vibrio 

 is not a single definite organism, but that cholera may be 

 caused by any one of a group of closely allied vibrios. 



Toxins. Brieger in 1887 obtained cadaverin and pu- 

 trescin and two other basic bodies from cholera cultures. 

 Brieger and Frankel isolated a tox-albumin, and Gamaleia 

 a ferment-like body. Hueppe believes that the cholera 



1 Arbeit, a. d. Kais. Gesundheitsamte, xxvi, 1907, p. 536. 



