10 THE AMOEBAE LIVING IN MAN 



done by the Italians— Grassi (1879 — 1888), Calandruccio (1890), Celli 

 and Fiocca (1894, 1895), Casagrandi and Barbagallo (1895, 1897) — whose 

 observations were in many cases perfectly correct, but unfortunately 

 marred by their failure to recognize the existence of more than one 

 species of amoeba in man. They identified all their amoebae with 

 those of Losch, whereas they were really those studied by Lewis and 

 Cunningham ; and they wrongly concluded, from their investigation 

 of a harmless species, that all intestinal amoebae are equally harmless. 



Losch's amoebae were studied, during the same period, by many 

 other woikers. Among these Kartulis (1885 — 1893), Councilman and 

 Lafleur (1891), Kovacs (1892), and Kruse and Pasquale (1894) must be 

 specially mentioned. To Councilman and Lafleur especially belongs 

 the credit of having first stated clearly that there is a particular kind of 

 dysentery caused by amoebae — "amoebic dysentery," as they first called 

 it. Before their time there were workers — such as Kartulis — who 

 apparently believed that "dysentery" in general is invariably and 

 exclusively the result of amoebic infection. Councilman and Lafleur 

 also confirmed the observation of Kartulis (1887) that amoebic dysen- 

 tery may be followed or accompanied by the formation of hepatic 

 abscesses ; and that in such cases amoebae, apparently identical with 

 those found in the stools, may be present in the liver — as Koch* first 

 showed. That " tropical " hepatic abscess is definitely associated with 

 *' tropical " dysentery had, however, been recognized long before by the 

 Anglo-Indian clinicians, whose observations thus found their true 

 explanation. 



I do not know who first suggested that more than one species of 

 amoeba may inhabit the human bowel. Schuberg (1893) attributes the 

 idea to Kartulis (1891), but it was expressed also by Councilman and 

 Lafleur (1891) and Lutz (1891) at about the same time. Schuberg 

 himself, and Lutz, and most other workers at this period, concluded that 

 there was insufficient evidence to prove the existence of more than one 

 species. Councilman and Lafleur, it is true, believed in the existence 

 of more than one species, but they adduced no evidence in support of 

 their belief. This evidence, however, was promptly supplied by Quincke 

 and Roos {1893) ; but by one of those curious blunders which so often 

 arrest the progress of science, their observations were almost ignored 

 by their contemporaries, and never received the attention which they 

 merited. 



By the year 1897 all the main facts necessary for understanding the 

 relation of amoebae to dysentery had been discovered. It was clear 

 from the work of the bacteriologistsf that epidemic dysentery is usually 

 caused by bacteria and not by amoebae. It was equally clear, however, 

 that there is a particular kind of dysentery caused by amoebae — as the 

 work of Losch, Kartulis, Councilman and Lafleur, Kovdcs, Kruse and 

 Pasquale, and Quincke and Roos had demonstrated. It was, moreover, 

 evident, from the work of Grassi, Calandruccio, Celli and Fiocca, and 

 Casagrandi and Barbagallo, that all intestinal amoebae do not cause 

 dysentery. Furthermore, it had been shown by Quincke and Roos how 

 the different species of intestinal amoebae can be distinguished from 



* Vide Koch and Gafifky (1887). 



t Consult especially Janowski (1897) in this connexion. 



