452 BACILLUS OF MALIGNANT (EDEMA 



follows. The cultures possess a peculiar heavy, though not 

 putrid, odour. M 'In tosh finds that the organism ferments 

 glucose, maltose, and lactose, but not saccharose, inulin, glycerin, 

 or starch. His strains produced coagulation of milk, but 

 without any digestion of the casein, and caused no liquefaction 

 of coagulated serum ; in cooked meat medium there was no 

 change in colour. He accordingly places the organism in the 

 non-proteolytic group. Strains described by other observers, 

 however, both liquefy coagulated serum and digest milk. It is 

 manifest that further definition -of the organism is necessary. 

 Spore formation occurs in cultures above 20' C, and is usually 

 well seen within forty-eight hours at 37°C. 



Experimental Inoculation. — A considerable number of 

 animals — the guinea-pig, rabbit, dog, sheep, arid goat, for 

 example — are susceptible to inoculation with this organism. 

 There is general agreement as to its marked pathogenic 

 properties. Especially is this the case when the serous 

 exudate containing the bacillus is used for inoculation, a mere 

 fraction of a cubic centimetre being a fatal dose. M'Intosh 

 found that with his strains ■01 c.c. of a fluid culture injected 

 intramuscularly killed a guinea-pig within twenty-four hours. 



Subcutaneous inoculation with pure cultures produces in the 

 guinea-pig chiefly a widespread gelatinous oedema, and a blood- 

 stained serous fluid exudes from the affected part. The under- 

 lying muscles are softened and partly necrosed, and of bright 

 red colour ; but there is" little formation of gas, and putrid 

 odour is almost absent. The internal organs show little change. 

 The bacilli are present in the peritoneal fluid, and occur as long 

 motile filaments. They have sometimes been cultivated from 

 the blood, but they are always scanty. Infection with the 

 organism is said to occur frequently when a little garden-earth 

 is introduced subcntaneously in' the guinea-pig, but in this case 

 the local lesion presents a putrid character, owing to the presence 

 of other organisms. 



When the bacilli are injected into mice, however, they enter and 

 multiply in the blood stream, and they are found in considerable 

 numbers in the various organs, so that a condition not unlike 

 that of anthrax is found. The spleen also is much swollen. 



Immunity. — Malignant oedema was one of the first diseases 

 against which immunity was produced by injections of toxins. 

 The filtered cultures of the bacillus in sufficient doses produce 

 death with the same symptoms as those caused by the living 

 organisms, but a relatively large quantity is necessary. Chamber- 

 land and Eoux (1887) found that if guinea-pigs were injected 



