560 EXPERIMENTAL RESEARCHES WITH CHICKEN-CHOLERA MICROBES, 



inoculations of blood into normal rabbits. Besides, the appearance 

 of the organs was nearly always such as bearing a close resemblance 

 to that in the case of fowls and pigeons which succumb to the 

 disease. 



Certain results obtained in the foregoing experiments, would 

 seem to lead to the belief that indigenous birds, as exemplified by 

 a few instances, may not always necessarily become affected or 

 killed by taking up, along with food, certain small or minute 

 quantities of the microbes derived, we had better add, directly 

 from the bodies of rabbits newly dead of " chicken-cholera.'*' On 

 the other hand, inoculation with the virus taken from the same 

 source, may be looked upon as a far more dangerous, although 

 naturally more rarely occurring, mode of infection for such birds. 

 Further below I shall mention a corresponding case in common 

 pigeons. 



(10.) Indigenous Crows. 



At my request, Mr. Taylor, of the Rabbit Branch, Lands 

 Department, Sydney, caused a number of indigenous crows to 

 be caught near Hay, New South Wales, and to be forwarded to 

 me. On the 8th and 10th November, 1888, I received them, 

 eight in all, of which, however, two died soon after arrival. The 

 remaining six appeared in good health, although at first they were 

 a little sluggish. They belonged to the species Corone australis, 

 Gould ; found all over Australia, including Tasmania. I am told 

 that there is very little difference between the two species of 

 crows described from Australia ; one is the above-mentioned, and 

 the other is Corvus corondides, Yig. and Horsf., which is said not 

 to occur in Tasmania. 



I enumerate the experiments upon the six crows in chrono- 

 logical order : — 



1888. 

 (i) November 13th, 11 a.m. 



Two of the crows, kept in one box with plenty of space in it, were 

 inoculated (under the skin over the pectoral muscle on one side) with 

 fresh virulent liver-blood taken from a rabbit which died of " chicken- 

 cholera " on inoculation. 



