522 EXPERIMENTAL RESEARCHES WITH CHICKEN-CHOLERA MICROBES, 



are accustomed to find in poultry affected with chicken-cholera. 

 " Chicken-cholera " of rabbits has the character of a pure, most 

 acute septicaemia, and is not a septicaemia in combination with 

 " typhoid," as in poultry. In the judgment of the results obtained 

 from certain experiments, we shall have to take this fact into 

 consideration.! 



History of Experiments on a Tame Rabbit. 

 1888. 

 (a) August 16th, 11.30 a.m. 



A tame rabbit (^f , full-grown, long-haired albino, of the Angora type ; 

 not treated so far with '-chicken-cholera" or anything similar) was fedy 

 together with another tame, long-haired black i^abbit (in one box), on 

 cabbage-leaves infected with 3 ccm. of a virulent broth-culture of the 

 chicken-cholera microbes. Both began to eat at once and had quickly 

 finished eating the portion. 



Results : 



The black specimen was found dead (from " chicken cholera ") at 

 8.45 p.m., August 18th (again mentioned under "Experiments on 

 Hares," p. 569). 



1 1 regret not to have had at my disposal active cultures of the microbes 

 of Koch's rabbitsepticsemia. Dr. Fischer, of Sydney, handed me on the 

 7th July, 1888, Agar-Agar-cultures of these microbes, which he had brought 

 from Koch's Laboratory when in BerUn some time before. On examination, 

 however, they were found to have lost their vitality. 



I should have liked to study such bacteria side by side with the; bacteria 

 of chicken-cholera. The difiference, so far made out between the two, is 

 one of degree rather than of kind. 



In the blood of the rabbits (as well as in other animals which in my 

 experiments died of chicken-cholera, see below) the bacteria, in properly 

 stained cover-glass preparations, appeared in the shape of the well-known 

 rods which showed only the ends deeply coloured, while a middle portion 

 presented itself as a colourless spot, with delicate^ coloured lines 

 laterally. 



In liver-blood of rabbits dead of "chicken-cholera," I repeatedly observed 

 that among the large numbers of typical microbes, there occurred, here and 

 there, rather anomalous forms, which had about the same outlines, and 

 behaved towards methylene-blue in the same way as those typical forms, 

 but which were very considerably larger. Their length was up to 0'004 

 mm, (cover-glass preparations), their width about a third of length. 



