BLACK QUARTER 525 



fluid slender bacilli are present, some of which are swollen or 

 club-shaped from the presence of spores. The muscles are dark, 

 slightly crepitant owing to the presence of gas, and have a rancid 

 odour. 



The organism, the B. (Clostridium) chauvcei, is a slender rod 

 never forming long threads, is strictly anaerobic and motile but 

 loses its motility in the presence of oxygen. Some of the rods are 

 cylindrical throughout, others form slender spindles, others are 

 oval or lemon-shaped. In broth and meat media clostridial forms 

 and rods with sub -terminal spores occur. It stains in the tissues 

 by Gram's method, but tends to be Gram-negative in culture. 



Gelatin is rapidly liquefied, serum is not liquefied. In glucose- 

 agar it forms a thick, irregular, greyish growth, with much 

 development of foul-smelling gas. It forms acid and clot in milk 

 and acidifies meat broth without blackening. B. chauvcei ferments 

 glucose, lactose, maltose and sucrose, but not salicin, inulin and 

 the alcohols. The colonies are round or lenticular with regular 

 margins. The writer has found extreme difficulty in isolating 

 and in maintaining cultures of the organism. The guinea-pig is 

 susceptible if inoculated subcutaneously or into the muscles, 

 the bacilli being found at the seat of inoculation, but not in the 

 blood or internal organs. Mice are also susceptible, but rabbits 

 are relatively insusceptible. Artificial immunity can be induced 

 in various ways : by bacilli attenuated by heat or by successive 

 cultivations, or by heating the dried muscle to 85 to 90 C. for 

 six hours (Kitt), also by inoculating the susceptible animal at the 

 tip of the tail. Hanna, 1 by growing the organism in a mixture of 

 blood-serum and broth, obtained toxins which, by careful injection, 

 conferred immunity on rabbits, the animals after injection yielding 

 an antitoxic serum. 



Hamilton described anaerobic bacilli in braxy, louping-ill, 

 and other diseases of sheep and deer, but they are probably putre- 

 factive and non-specific. 



Animals suffer considerably from acute gangrenous infections. 

 Malignant osdema and black quarter infections are relatively 

 common. B. perfringens infections are very rare and B. cedema- 

 tiens infections are rare, except, perhaps, in the horse. 2 



1 Journ. Path, and Bact., vol. iv, 1897, p. 383. 



2 Heller, Journ. Infectious Diseases, vol. 27, 1920, p. 385 (Bibliog.). 



