,-j22 bacteriology. 



lished, the circulating blood contains a body, antitoxin, 

 that combines directly with tetanus toxin in a test-tube, 

 and thereby renders it pliysiologically inactive (non-in- 

 toxicating) ; and the serum of the immune animal is 

 not only capable of protecting non-immune, susceptible 

 animals from the poisonous action of tetanus toxin 

 (within limits), but also against the effects of the living 

 tetanus bacillus as well. 



THE BACILLUS OF MALIGNANT CEDEMA. 



The bacillus of malignant oedema, also known as 

 vibrion septique, is another pathogenic form almost 

 everywhere present in the soil. In certain respects it 

 is a little like the bacillus of anthrax, and was at one 

 time confounded with it ; but it differs in the marked 

 peculiarity of being a strict anaerobe. It was first 

 observed by Pasteur, but it was not until later that 

 Koch, Liborious, Kitt, and others described its pecu- 

 liarities in detail. It can often be obtained by 

 inserting under the skin of rabbits or guinea-pigs small 

 portions of garden-earth, street-dust, or decomposing 

 organic substances. There results a widespread oedema, 

 with more or less gas-production in the tissues. In 

 the (Edematous fluid about the site of inoculation the 

 organism under consideration may be detected. (Fig. 

 98, A.) 



It is a rod about 3 to 3.5 fi long and from 1 to 1.1 ;U 

 thick — i. e., it is about as long as bacillus anthracis, but 

 is a trifle more slender. It is usually found in pairs, 

 joined end to end, but may occur as longer threads; 

 jiiu'ticularly is this the case in cultures. When in pairs 

 the ends that approximate are squarely cut, while the 

 distal extremities are rounded, When occurring singly 



