ON THE ACTION OF CERTAIN BACTERIA 7 



acid and gas in media containing dulcit. Attention may be drawn to 

 the animal experiments in the case of guinea-pigs i and 4. It would 

 appear that a cutaneous infection can take place by using the method of 

 Albrecht and Ghon. In the case of guinea-pig 6, a chronic form of the 

 disease was produced, although it is possible that by varying the experi- 

 mental conditions, e.g., by raising the virulence of the bacillus artificially, 

 an acute condition, resulting fatally in a few days, might be brought 

 about. Unfortunately, lack of time from pressure of other work 

 rendered it impossible to carry out further experiments in this direction. 

 The significance of the cutaneous method of infection will be referred 

 to later. 



It may appear somewhat curious that, although the disease shows 

 well-marked lesions, very little can be found concerning it on consulting 

 the literature. Nocard and L^clainche in their classical work on the 

 microbic diseases of animals (edition 1903) make no mention of it. 

 MacConkey (i), in a foot-note to a recent paper dealing with lactose- 

 fermenting organisms, gives a brief description of its main features. He 

 notes that an organism indistinguishable from B. enteritidis (Gsertner) 

 seemed to be the cause of a small epidemic amongst the experimental 

 guinea-pigs at the Serum Institute of the Lister Institute near London, 

 and refers to the resemblances of the naked-eye appearances to those of 

 pseudo-tuberculosis rodentium. 



Kovarzik (2) has given an account of an epizootic, amongst guinea- 

 pigs, which he ascribed to a variety of B. coli. Lehmann and Neumann, 

 however, include the bacillus in the B. enteritidis (Gsertner) group. The 

 principal points of his paper may be briefly summarised. Post mortem — 

 there were found greyish-white necrotic foci on the surface of the liver 

 and spleen. In smears of these organs the bacilli were isolated, but 

 sometimes occurred in pairs — short rods (Gram-negative) with rounded 

 ends. Coccal forms occurring in cultures ; giving on agar, greyish-white 

 glancing colonies, bluish by transmitted light, later white ; gelatine not 

 liquefied ; acid and gas in glucose ; no clotting of milk nor indol 

 reaction. Cultures were very pathogenic to guinea-pigs, especially 

 when inoculated intraperitoneally — an infection was also produced 

 through the intact conjunctiva. It was pathogenic to rabbits by intra- 

 venous but not by subcutaneous inoculation, and killed also by injection 

 into the large intestine. Gray rats were killed by feeding on cultures — 



(293) 



