SWINE PLAGUE. 379 



to the disease and to death, the symptoms being the 

 same as in spontaneous cases. It is especially fatal to 

 the white race (improved breed, most highly valued by 

 those who raise pigs). 



" III. In 1878 Dr. Klein, of London, published an 

 elaborate research upon this disease, which he calls 

 infectious pneumo-enteritis of the pig ; but this author 

 has been entirely mistaken as to the nature and proper- 

 ties of the parasite. He has described a bacillus with 

 spores as the microbe of this disease, which he describes 

 as being even larger than Bacillus anthracis (la bacteride 

 du charbori). This is very different from the true mi- 

 crobe of swine plague, and has no relation to the etiol- 

 ogy of the disease. 



" IV. After assuring ourselves, by direct proof, that 

 the disease does not recur, we have succeeded in in- 

 oculating it in a mild form, and the animal has subse- 

 quently proved to be protected against the malignant 

 form of the disease." 



Neguin and Salmon had previously reported 

 their failure to find the bacillus of Klein in the 

 blood and other infectious fluids obtained from ani- 

 mals sick with this disease, and the constant pres- 

 ence of a minute micrococcus apparently identical 

 with that described by Pasteur. 



Salmon says that blood drawn from the veins of 

 a pig affected with swine-plague into " capillary 

 vacuum tubes " was quite free from bacilli at the 

 end of ten days. But this blood swarmed with 

 micrococci, single, in pairs (Pasteur's Fig. 8), in 

 chains, and in zoogloea masses. Healthy pigs in- 

 oculated with this blood sickened at the end of 

 seven days and exhibited the characteristic symp- 



