20 QUATERCENTENARY STUDIES IN PATHOLOGY 



In acute cases, after the period of incubation, the animal hunches 

 itself up in a corner of the cage, refuses to eat, and, when disturbed, moves 

 in an inco-ordinate manner, as if suffering from alcoholic intoxication. 

 Convulsions are frequent just before death, which appears to be due to 

 collapse. 



In chronic cases the early symptoms are less acute, the animal 

 gradually loses flesh till a profound state of marasmus may result. In 

 some of the rats suffering from chronic toxaemia following the injection 

 of toxic filtrates, we have observed a form of paralysis resembling 

 diphtheria paralysis in the guinea-pig. The hind limbs are first affected, 

 then the fore limbs, and ultimately the respiratory muscles may be 

 involved. These animals are often greatly emaciated. Convulsions 

 frequently occur immediately before death. 



Post-mortem Changes observed in Animals dying of Toxcemia. — In the 

 animals which die of acute toxaemia, say within 24 hours after sub- 

 cutaneous injection of a toxin, the most marked feature is oedema round 

 the site of inoculation. This may be very extensive, affecting the whole 

 abdominal wall, and small haemorrhages are sometimes present. The 

 neighbouring lymphatic glands may be enlarged. Haemorrhages are 

 sometimes present in the viscera, especially where the injection has been 

 intraperitoneal, in which case the peritoneum and the mucous membrane 

 of the alimentary canal are injected or haemorrhagic. 



In the animals which survive several days or weeks, wasting of the 

 musculature is a marked feature. Fatty degeneration of the liver is a 

 frequent lesion, and necrotic areas are present in a few of the cases. 

 Where death occurs at a late period the spleen may be enlarged. 



The Question of a Plague Antitoxin. 



With the view of ascertaining whether the injection of toxic filtrates 

 would stimulate the animal body to antitoxin production, two horses 

 were specially employed for immunisation with the filtrates of cultures. 

 In the case of one, the horse " R " filtrates from bouillon cultures, 

 which had been heated to 70" C. for one hour, were alone used. This 

 animal, in the three months preceding the removal of the blood, the 

 serum from which was tested, received injections amounting to 1080 

 c.c. of filtrates. 



