PHAGOCYTOSIS 37 



neutralised by their antisera, unit for unit, according 

 to the law of multiples. Now, however, in the case 

 of the vast majority of pathogenic bacteria, which 

 belong to the class of micro-organisms which owe 

 their toxicity to the endotoxins contained within their 

 bodies, these latter poisons are said to be liberated 

 from the dead organisms during their disintegra- 

 tion or during autolysis. These endotoxins are 

 recognised by the fact that they do not call out 

 true antitoxins which become free in the plasma and 

 serum, but do, nevertheless, lead to the formation of 

 digestive antibodies, these not, however, following 

 the " law of multiples " in protecting infected animals 

 from the poisons. The liberation of these poisons by 

 the destruction of the bacteria in the animal body is 

 well illustrated by the so-called phenomenon of 

 Pfeiffer which takes place when cholera vibrios and 

 immune cholera serum are introduced into the 

 peritoneal cavity of a guinea-pig. If specimens are 

 withdrawn from time to time, a rapid swelling up, 

 disintegration, and disappearance of the vibrios can 

 readily be demonstrated. 



The power of disintegration is also claimed for the 

 body fluids of normal animals, and is supposed to be 

 demonstrated by the following experiment. When 

 graded quantities of a fresh cholera culture are intro- 

 duced into the peritoneal cavity of normal guinea- 

 pigs of equal weight the following phonemena can be 

 observed : Minimal doses of the culture produce a 

 febrile condition which continues for a few hours with 



