288 BACTERIOLOGY. 



medium for cultivating the bacillus, die in a few 

 days. Goats, hedgehogs, sparrows, cows, horses, 

 are all susceptible. Rats are infected with difficulty. 

 Pigs, dogs, cats, white rats, and Algerian sheep 

 have an immunity from the disease. Frogs and 

 fish have been rendered susceptible by raising the 

 temperature of the water in which they lived. 



Dissemination of the disease and mode of infection. It 

 has been stated that when carcases of animals which 

 have died of anthrax are buried under the soil, the 

 development of the bacilli into spores can take place. 

 The spores were supposed to be taken up by earth 

 worms, carried to the surface, and deposited in their 

 castings ; animals then grazing or sojourning on 

 the soil are thus liable to be infected.* This has not 

 been borne out by experiment.! Bacilli, however, 

 occur in large numbers in the blood and discharges 

 from the nose and mouth of the moribund animals, 

 and in the urine and faeces. They find a nourishing 

 soil in decaying vegetable and animal matter, and 

 having free access of oxygen form copious spores, 

 so that the grass is extensively contaminated. 



In warm and marshy districts the spore-formation 

 is still more active, and the spores may be carried 

 by floods over adjacent meadows. As to the mode 

 of infection, the animals may be directly infected 

 through buccal wounds caused by siliceous grasses, 

 or by wounds of insects ; the intestinal and pul- 



* Pasteur, Bulletin de VAcademie de Medecine. 1880. 

 t Koch, Mittheil. a.d. Gesundheitsamte. 1881 



