446 MALIGNANT (EDEMA 



may be added, however, that if the characteristic forms are 

 not seen on microscopic examination of the material from the 

 wound, they may often be found by inoculating a deep tube of 

 one of the glucose media with such material, and incubating for 

 forty-eight hours at 37 C. At the end of this period, spore- 

 bearing tetanus bacilli may be detected microscopically, though 

 of course mixed with other organisms. 



(c) Inoculation. Mice and guinea-pigs are the most suitable 

 animals. Inoculation with the material from a wound should 

 be made subcutaneously. A loopful of the discharge introduced 

 at the root of the tail in a mouse will soon give rise to the 

 characteristic symptoms, if tetanus bacilli are present. With 

 suspicious organisms isolated by culture it is well to use the 

 splinter method (p. 436), as some strains of the b. tetani tend to 

 produce little toxin in artificial media, and may be injected 

 without causing tetanic symptoms. 



MALIGNANT (EDEMA (Septicemie de Pasteur). 



The organism now usually known as the bacillus of malignant 

 oedema is the same as that first discovered by Pasteur in putrefy- 

 ing carcases, and named by him vibrion septique. He described 

 its characters, distinguishing it from the anthrax bacillus, which 

 it somewhat resembles morphologically, and also the lesions 

 produced by it. He found that it grew only in anaerobic 

 conditions, but was able to cultivate it merely in an impure 

 state. It was more fully studied by Koch, who called it the 

 bacillus of malignant oedema, and pointed out that the disease 

 produced by it is not really of the nature of a septicaemia, as 

 immediately after death the blood is practically free from the 

 bacilli. 



"Malignant oedema" in the human subject is usually 

 described as a spreading inflammatory oadema attended with 

 emphysema, and ultimately followed by gangrene of the skin 

 and subjacent parts. In many cases of this nature the bacillus 

 of malignant oedema is present, associated with other organisms 

 which aid its spread, whilst in others it may be absent. One of 

 us has, however, observed a case in which the bacillus was 

 present in pure condition. Here there occurred intense oedema 

 with swelling and induration of the tissues, and the formation 

 of vesicles on the skin. Those changes were attended with a 

 reddish discoloration afterwards becoming livid. Emphysema 

 was not recognisable until the limb was incised, when it was 

 detected, though in small degree. Further, the tissues had a 



