868 president's address. 



organism, formed very differently from that of the septicoemia, a 

 Micrococcus. Believing that this must be the cause of the 

 gangrene, he succeeded in separating it from the bacillus of the 

 septicoemia. Koch found that the bacillus of the septicoemia 

 produced in the domestic mouse would not produce that disease in 

 the field mouse, but the Micrococcus of the gangrene, &c, did 

 develop among its tissues, and when this newly-developed micro- 

 coccus was inoculated into another mouse, it developed gangrene 

 pure and simple. Koch inoculated a rabbit with a putrid liquid, 

 which produced a special erysipelatous inflammation, and in this 

 inflammation he discovered another exquisitely delicate bacillus, 

 resembling the micrococcus of the gangrene in its development, 

 and concluded that it constituted the Materies MorhiP 



Professor Liston also refers to another micro-organism dis- 

 covered by Toussaint, and which has been made the subject of 

 special investigation by M. Pasteur — the so-called Cholera des 

 poules, characterized by great swellings of thee hain of lymphatic 

 glands in the vicinity of the windpipe of the fowl, inflammation, 

 and effusion into the pericardium, and congestion, and it may be 

 ulceration of the duodenum. It is a blood disease, highly 

 infectious. If the blood or excreta of diseased chickens be mixed 

 with the food of other healthy chickens, four out of six are affected 

 and die. It is supposed that it is communicated by the artificially 

 diseased food passing over an abrasion in the lining surface of 

 the mouth or throat, as the disease is at once produced by inocu- 

 lating a chicken in the mouth with the blood of a diseased fowl. 

 M. Pasteur found that this micro-organism could be readily 

 cultivated outside the body of the fowl, not in every medium but 

 luxuriantly in chicken broth, and in infusions of meat. The 

 transverse diameter of this bactarium is about 1*50,000 to 

 1-25,000 of an inch. Pasteur found that this bacterium could be 

 produced in any number of successive cultivations, and yet retain 

 its full virulence. A healthy chicken being inoculated with it, 

 was as surely affected with the disease as if inoculated with the 



