6 PARASITIC AMCEB.E OF MAN. 



Entamoeba histolytica, they compared the clinical 

 differences between amoebic dysentery and catarrhal 

 dysentery, as well as the differences in the patho- 

 logical lesions of the two diseases. They proposed 

 the name Amoeba dy sentence for the organism asso- 

 ciated with the lesions which they described, and 

 clearly recognized that other, and perhaps non- 

 pathogenic amoeba?, might infest the intestine of man. 

 It is not too much to say that to these authors we 

 owe a large part of the interest which has been shown 

 in the study of dysentery during recent years. 



From 1891 to 1893 confirmatory studies ap- 

 peared by Cahen, Lutz, Kovacs, and Quincke and 

 Roos. The latter authors, whose work was done at 

 Kiel, concluded that there were at least two varieties 

 of pathogenic amoeba? as well as one variety which 

 was non-pathogenic. In view of the recent separation 

 of two species of pathogenic amoeba?, Entamoeba 

 Mstolytica and Entamoeba tetragena, these observa- 

 tions of Quincke and Roos are of interest, as it is 

 possible that these authors were the first to differ- 

 entiate these two species. 



In 1894, Kruse and Pasquale, who studied amoebic 

 dysentery in Alexandria, Egypt, confirmed the work 

 of Councilman and Lafleur and considered that there 

 existed two species of amoebae, one pathogenic and 

 the other a harmless inhabitant of the intestinal tract. 



