310 BACTERIOLOGY. 



fever, the results of inoculation of animals with cultures 

 of this organism cannot be safely predicted. According 

 to the observations of Escherich, Emmerich, Weisser, and 

 others, the results that do appear are in most instances 

 to be attributed to the toxic rather than to the infective 

 properties of the culture used. 



When introduced into the subcutaneous tissues of 

 mice it has no effect, while similar inoculations of 

 guinea-pigs are sometimes (not always) followed by 

 abscess formation at the point of injury, or by altera- 

 tions very similar to those produced by intra-vascular 

 inoculation, viz.: death in less than twenty-four hours, 

 accompanied by redness of the peritoneum and marked 

 hypersemia and ecchymoses of the small intestine ; 

 together with swelling of Peyer's patches. The csecum 

 and colon may remain unchanged or present enlarged 

 follicles. There may or may not be an accumulation 

 of fluid in the abdominal cavity, but peritonitis is 

 rarely present. The small intestines may contain 

 bloody mucus. 



Intra-venous inoculation of rabbits may be followed 

 by similar changes with often the occurrence of diar- 

 rhoea before death, which may, in the acute cases, result 

 in from three to forty hours. In another group of 

 cases acute fatal intoxication does not result, and the 

 animal lives for weeks or months, dying ultimately of 

 what appears to be the effects of a slow or chronic form 

 of infection. For a few hours after inoculation these 

 animals present no marked symptoms ; exceptionally 

 somnolence and diarrhoea have been observed at this 

 period, indicating acute intoxication from which the 

 animal has recovered. The affection is unattended by 

 fever. The most marked symptom is loss of weight. 



