286 PROTECTIVE INOCULATIONS. 



wings and ruffled feathers, remains standing in one place until it dies. 

 Infection may also occur from the ingestion of food moistened with a 

 culture of the bacillus or soiled with the discharges from the bowels 

 of other infected fowls. At the autopsy the mucous membrane of the 

 small intestine is found to be inflamed and studded with small hem- 

 orrhagic foci, as are also the serous membranes ; the spleen is notably 

 enlarged. The bacilli are found in great numbers in the blood, in the 

 various organs, and in the contents of the intestine. In rabbits death 

 commonly occurs in from sixteen to twenty hours, and is often pre- 

 ceded by convulsions. The temperature is elevated at first, but 

 shortly before death it is reduced below the normal. The post-mor- 

 tem appearances are : swelling of the spleen and lymphatic glands ; 

 ecchymoses or diffuse hemorrhagic infiltrations of the mucous mem- 

 branes of the digestive and respiratory passages, and in the 

 muscles ; and at the point of inoculation a slight amount of inflamma- 

 tory oedema. The bacilli are found in considerable numbers in the 

 blood within the vessels, or in that which has escaped into the tissues 

 by the rupture of small veins. They are not, however, so numerous 

 as in some other forms of septicaemia e.g., anthrax, mouse septi- 

 caemia when an examination is made immediately after death ; later, 

 the number may be greatly increased as a result of post-mortem mul- 

 tiplication within the vessels. The rabbit is so extremely susceptible 

 to infection by this bacillus that inoculation in the cornea by a slight 

 superficial wound usually gives rise to general infection and death. 

 This animal may also be infected by the ingestion of food contami- 

 nated with a culture of the bacillus. It is by this means that Pasteur 

 proposed to destroy the rabbits in Australia, which have multiplied 

 in that county to such an extent as to constitute a veritable pest. 

 Both in fowls and in rabbits the disease may, under certain circum- 

 stances, run a more protracted course e.</., when they are inoculated 

 with a small quantity of an attenuated culture. In less susceptible 

 animals guinea-pigs, sheep, dogs, horses a local abscess, without 

 general infection, may result from the subcutaneous injection of the 

 bacillus ; but these animals are not entirely immune. In the infec- 

 tious maladies of swine, cattle, deer, and other large animals, to 

 which reference has been made, and which are believed to be due to 

 the same bacillus, the symptoms and pathological appearances do not 

 entirely correspond with those in the rabbit or the fowl ; but the ba- 

 cillus as obtained from the blood of such animals corresponds in its 

 morphological and biological characters with Pasteur's microbe of 

 fowl cholera, and Koch's bacillus of rabbit septicaemia, and pure 

 cultures from the various sources mentioned are equally fatal to rab- 



