558 EXPERIMENTAL RESEARCHES WITH CHICKEN-CHOLERA MICROBES, 



From the results so far obtained we see that the virus of 

 chicken-cholera, derived, as it was, in the shape of blood from rabbits 

 which died in consequence of infection by that virus, proved, when 

 caused to gain entrance into the digestive organs in the noted quan- 

 tities, fatal to the magpies, butcher-birds, and blue-jay (which are 

 principally animal feeders), to the wonga- and bronze-wing pigeons, 

 to the gallahs and quail (which are all of them vegetable feeders). 

 One of the wonga-pigeons, however, and one of the quail, did not 

 succumb until after having been fed a second time on somewhat 

 larger portions of the virus than before. One of the gallahs, 

 although surviving two experiments by feeding, perished quickly 

 in consequence of inoculation, thus manifesting its ready suscepti- 

 bility to inoculated chicken-cholera. 



Of two laughing-jackasses (true animal-feeders), one died after 

 the first experiment (feeding), but not of chicken-cholera, as shown 

 by the result of the post-mortem examination. The other sur- 

 vived feeding on virulent material for two successive times ; but 

 when inoculated later on, it succumbed, we are entitled to say, to 

 this disease, in so far as evidenced by the occurrence of numerous 

 bacteria of chicken-cholera in the blood, by their successful culti- 

 vation, and inoculation into a healthy rabbit, which died as usual. 

 The appearance of the organs was less characteristic than is 

 usually the case with birds dead of the disease. 



Two wekas (animal-feeders), of which one was once fed and 

 twice inoculated, the other twice fed and once inoculated, remained 

 alive. Whether their insusceptibility arose from the fact of their 

 having been possibly treated preventively at first, or whether — 

 what seems to me to be not at all impossible — birds of this 

 description are naturally immune against chicken-cholera in any 

 shape of application, can only be decided by further experiments. 



Nearly five and a half months later, the two wekas (rooster 

 and hen) were subjected to a last inoculation, this time of a con- 

 siderably larger quantity of virulent blood from a "chicken-cholera'' 

 rabbit [see Table YI. {d)\ The result was that the weka-hen 



