388 CHOLERA. 



numbers in the blood and also in the small intestine, but with 

 smaller doses they are practically confined to the peritoneum. 

 Kolle found that when the minimum lethal dose was used 

 in guinea-pigs, the peritoneum might be free from organisms 

 at the time of death, the fatal result having taken place 

 from an intoxication. In rabbits, after intravenous injec- 

 tion of comparatively large quantities, death may follow 

 within eighteen hours, with symptoms of general intoxica- 

 tion ; the organisms are present in the blood, though 

 rather diminished in number, and few are to be found in 

 the intestine. If, however, the dose is smaller and the 

 animals live longer, then the organisms may settle and 

 multiply in the intestine, and changes quite analogous to 

 those in cholera are produced congestion of mucous 

 membrane, and at places desquamation of epithelium 

 (Issaeff and Kolle). In the case of animals which die when 

 these changes have occurred, the organisms may have 

 quite disappeared from the blood and internal organs. 

 These experiments show that though the organisms 

 undergo a certain amount of multiplication when introduced 

 by the channels mentioned, still the tendency to invade 

 the tissues is not a marked one. On the other hand 

 the symptoms of general intoxication are always pro- 

 nounced. Hence arise questions as to the nature and 

 mode of action of toxic bodies produced by the cholera 

 organism. 



Toxines. Though there is no doubt that there are 

 formed by Koch's spirillum toxic bodies which produce 

 many of the symptoms of cholera, there is at present very 

 little satisfactory knowledge regarding their chemical nature. 

 The following summary may be given. 



It has been shown, especially by R. Pfeiffer, 1 that toxic 

 phenomena can be produced by injection of the dead 

 vibrios into animals. A certain quantity of a young 

 culture on agar, killed by exposure to the vapour of 



1 Pfeiffer obtained his earlier results with a vibrio from Massowah, 

 which is now known not to be a true cholera organism. This fact shows 

 that the effects described are not specific to the latter. 



