STUDIES ON FOWL CHOLERA 



285 



In the results of this test it appears that a reaction closely 

 simulating an anaphylactic shock resulted from the inoculation 

 of the second filtrate. The result was not fatal, however, and 

 it may be questioned whether it was due to the presence of an 

 exotoxin or to some other factor at present unrecognized. 



In view, however, of the discrepancy between the first and 

 second tests, a third experiment was undertaken in which use 

 was made of a still larger amount of filtrate from a six-day 

 chicken broth culture passed through a Berkefeld N-candle. 

 The filtrate was tested for sterility, and divided into two portions, 

 one of which was incubated over night and the other placed in 

 the ice-box. A slight haziness developed in the incubator tubes 

 and subcultures were made in chicken broth. These, however, 

 remained sterile. A 1314-gram rabbit was accordingly inocu- 

 lated intravenously with 1.5 cc. of the incubator filtrate. No 

 sign of illness followed within the following twenty-four hours 

 during which the animal was under observation. 



