1911.] Cultivating the Mycobacterium enteritidis, etc. 521 



of acid-fast bacilli. The specimen was fresh, and cultures were made 

 directly on to all the ordinary laboratory media. Fresh extracts of various 

 glands and organs (including the intestine) of normal bovines were also 

 prepared, and sterilised by passing through a Doulton white filter. The 

 extracts thus sterilised were placed in sterile tubes plugged with cotton 

 wool, and inoculated with the diseased material. Small sterile portions 

 of bovine organs were also obtained, placed in sterile tubes, and inoculated. 

 The above media were tested in various combinations, both with and 

 without glycerin, cholesterin, various sugars, fresh blood, and other 

 substances. The cultures were made aerobically and anaerobieally at 39° to 

 40° C. On none of these media were we able to obtain any definite growth 

 of the specific bacillus. 



Some experiments were also conducted to test the possibility of an ultra- 

 microscopic virus working in symbiosis with Johne's bacillus. Extracts of 

 bovine intestine infected with the disease were prepared and passed through 

 a Doulton white filter. The sterile filtrate so obtained was added to the 

 various media, and the whole inoculated with portions of intestine containing 

 living Johne's bacilli. These experiments all gave negative results. 



From the experiments conducted on this case we came to the conclusion 

 arrived at by most other workers, namely, that the specific bacillus would 

 not grow on any artificial medium known to bacteriologists, and that if 

 successful cultivation were to be achieved some new medium would have to 

 be prepared. We considered also that the failure of growth of the specific 

 bacillus must be due, either to some substance in the medium acting as a 

 poison, or to the absence of some material or foodstuff necessary for its 

 vitality and growth. 



On considering the question further, we were struck by the apparent 

 close relationship existing between this micro-organism and the tubercle 

 bacillus; and since the bacillus of pseudo-tuberculous enteritis and the 

 tubercle bacillus both grow in the same species of animal, we considered it 

 highly improbable that there could be any substance in the ordinary 

 laboratory media which would act as a poison to the one bacillus and not to 

 the other. This possibility was accordingly excluded, and we were forced to 

 conclude that the failure to grow the bacillus must be due to the absence of 

 some necessary foodstuff. 



Considering again the apparent close relationship between the tubercle 

 bacillus and the bacillus of pseudo-tuberculous enteritis, and the fact that 

 both these bacilli live in the bodies of bovines, we judged it probable that 

 they would require the same chemical substances for building up their 

 protoplasm, certain of which substances could be elaborated from artificial 



