262 MICROBIOLOGY 



and spleens. From the original cultures little difficulty is 

 experienced in cultivating the organism on glycerin agar, 

 fresh dog serum, Dorset's egg medium, potato, and glycerin 

 bouillon. The first cultures in glycerin bouillon made from 

 an original glycerin agar culture from the liver are charac- 

 terized by a grayish, somewhat viscid mass that develops 

 somewhat slowly in the bottom of the flask, but gradually 

 clouds the liquid throughout. Later generations develop a 

 thin, grayish, wrinkled pellicle which thickens and becomes a 

 porcelain white, dense, but somewhat friable, membrane on the 

 surface. 



The colonies on glycerin agar may vary from one to three 

 millimeters in diameter. The central portion is raised and of 

 a slightly yellowish tint as observed under a hand lens. This 

 central part is surrounded by a fiat expansion, about two- 

 thirds the thickness of the center, varying from one-half to 

 one millimeter in width, with ray-like projections radiating 

 from it and extending into the outer and very thin band of 

 growth with a lobulated margin. A pinkish tint to the 

 growth has been described. 



Nocard produced tuberculosis in fowls by inoculating 

 them in the peritoneal cavity with a small quantity of caseous 

 material taken from the bronchial gland of a tuberculous cow. 



Bacterium of fish tuberculosis. This bacterium, isolated 

 by Dubarre and Terre, 34 resembles Bacterium tuberculosis in 

 morphology and in a certain degree of acid-fastness. It grows 

 at low temperature, 15 to 30 C. It is non-pathogenic for 

 animals, but kills frogs within a month. Except for the acid- 

 fastness it has little in common with the organism of tuber- 

 culosis. 



Vaccination against tuberculosis. A large number of 

 men have tried to produce a vaccine with which to immunize 

 cattle against tuberculosis but as yet their efforts have not been 

 satisfactory. Individual animals may be made more resistant 

 for a time by vaccination but the methods proposed can not 



34 Dubarre et Terre. Comp. rendu de la Soc. de Biol., 1897. 



