METSCHNIKOFF'S VIBRIO. 183 



blood of diseased animals to be very poisonous. It is extra- 

 ordinarily easy to produce immunity against the bacteria, but 

 this does not increase the power of resisting the sterile poison. 

 The micrococci grow in immunised serum, but with reduction of 

 their virulence, which is restored, however, by inoculating fresh 

 bouillon. Hence, the serum would seem to contain antitoxine, 

 which neutralises the production of toxine by the growing 

 bacteria. 



MALIGNANT (EDEMA. 



Roux and CHAMBERLAND l found that cultures of the septic 

 vibrio freed from the micro-organisms were slightly poisonous, 

 while sterilised peritoneal fluid was very poisonous and had an 

 immunising power. But they also obtained "poisons" which 

 still had a very weak toxic action and some immunising power 

 after exposure to a temperature of 110 to 120 C. BESSON, 2 

 too, has prepared weak poisons (5 to 10 c.c. being required to 

 kill a guinea-pig) by filtering cultivations and in particular those 

 grown on flesh. 



SWINE PLAGUE. 



SiLBERSCHMiDT 3 discovered a weak poison with a specific 

 action in filtered cultivations. It was not completely destroyed 

 at 120 C., but was gradually weakened even at 60 C. The 

 filtrates produced immunity. 



SELBERG* found poisonous substances with a slight specific 

 action attached to the cells of the bacilli of swine plague. 



METSCHNIKOFFS VIBRIO. 



A very interesting report on this vibrio was published by 

 SANARELLi. 5 It grows vigorously on immunised serum after 

 first apparently dying, but is then almost completely innocuous, 

 though it again becomes toxic when grown in fresh bouillon. 

 In like manner the vibriones from an immunised animal can be 



1 Roux and Chamberland, "Immunit centre la septice'mie," Ann. Past., 

 ii., 561, 1887. 



2 Besson, "Contrib. a 1' etude du vibrion septique," Ann. Past., ix., 

 179, 1895. 



3 Silberschmidt, "Contrib. a 1'etude de la swine plague," A nn. Past., ix., 

 65, 1895. 



4 Selberg, "Beitr. z. Kenntn. d. Giftwirkung d. Schweineseuchen- 

 bakterien, &c.," Dies., Berlin, 1896. 



5 Sanarelli, "Defense de 1'organisme contre les microbes," Ann. Past., 

 vi., 225, 1892, 



