xij BACILLI : SPEClinCALLY PATHOGENIC 217 



Fowls, pigeons, and rabbits are unsusceptible to the 

 disease. 



As far as the appearances in gelatine plate and gelatine 

 streak go, there is a considerable similarity between the 

 microbe of grouse disease and bacillus coli ; this is also 

 strengthened by the fact that the former, like the latter, 

 forms gas bubbles in shake culture and curdles milk, the 

 difference being chiefly this— that the microbe of grouse 

 disease on subcutaneous injection is highly virulent to mice, 

 and particularly to the yellow-ammer; less so to guinea-pigs. 



h'lu. 74. — From a Section through the ic\m. arced Inguinal LvMi'i[-l Ii-and 

 01- A Pig dead of Swine Fever, 



1. A capillary Ijlood-ves^el Jllled with Ijacilli. 



2. Reticulum of adenoid tissue, 



3. A lymph-cell. 



Magnifying power 700. 



7. Bacillus of sK'iiic fevcr.~-T\\\s disease prevails largely 

 in this country ; in America it is known as hog cholera, on 

 the continent of Europe as swine plague. It is a liighly 

 infectious disease, spreading from animal to animal by air, 

 food, water, the lungs and bronchi and the intestines being 

 the chief places of disease, and containing the virus. The 

 infection is, under natural conditions, attriljutable to the 

 virus being derived from and spread by the expectoration of 

 the lungs and evacuations of the bowels. Alike by feeding. 



