EXPERIMENTAL INOCULATION 



647 



while they may be detected in the discharge a day or two later. 

 The action here on the tissues is of an analogous nature, namely, 

 a necrosis with softening and partial liquefaction, attended by 

 little or no suppurative change. The amoebae have also been 

 found in the sputum when a liver abscess has ruptured into the 

 lung, as not very infrequently happens. Kartulis records two 

 cases of brain abscess occurring secondarily to dysentery in which 

 numerous amoebae were present. 



Experimental Inoculation. Dysentery occurs occasionally in 

 animals, e.g., in monkeys, 

 but it is of comparatively 

 rare occurrence. The 

 disease sometimes results 

 in the dog by experimental 

 inoculation with dysen- 

 teric material. Kartulis, 

 for example, records two 

 cases, in one of which 

 liver abscess was present. 

 Cats are, however, found 

 to be more susceptible, 

 especially young animals. 

 Dysenteric changes have 

 been produced in this 

 animal by Kartulis, Kruse 

 and Pasquale, and others. FIG. 187. Section of wall of liver abscess, 

 The method generally showing an am ceba of spherical form with 

 , . , & . , J vacuolated protoplasm. From a case 



adopted is the mtroduc- published by Major D. G. Marshall, 

 tion of a small quantity xlOOO. 

 of mucus from a dysen- 

 teric case into the rectum. The resulting disease is of an acute 

 character, and sometimes leads to a fatal result. The changes in 

 the large intestine resemble those found in the human disease, 

 and microscopic examination shows the amoebae penetrating the 

 wall of the bowel in the characteristic manner. Kruse and 

 Pasquale obtained corresponding results when the material from 

 a liver abscess, containing amoebae without any other organisms, 

 was injected. Quincke and Roos obtained no effects when the 

 amoebae were administered by the mouth, but they obtained a 

 fatal result in two out of four cases when the cyst-like forms 

 were given. It is, however, not possible to state the species of 

 amoebae used in these experiments. Extremely important con- 

 firmatory evidence with regard to infection by the cysts of 

 E. histolytica has been supplied by experiments of Schaudinn. 



