AXENIC CULTIVATION OF ENTAMOEBA-DISPAR BRUMPT 1925, ENTAMOEBA-INSOLITA GEIMAN AND WICHTERMAN 1937 AND ENTAMOEBA-RANARUM GRASSI 1879

Three species of Entamoeba have been grown in axenic culture for the f irst time. In two cases, never methods for adapting the organisms to g rowth without bacteria were employed. While E. ranarum was axenized by the classic technique of Diamond, from a monoxenic culture with Trypa nosoma cruzi as the associate, both E. dispar and E. insolita were fir st grown in axenic culture medium supplemented with lethally irradiate d bacteria. From there, E. insolita was axenized directly, but E. disp ar initially required the presence of fixed bacteria. After prolonged culture under this technically axenic but unwieldy culture system, E. dispar was eventually adapted to growth in the absence of added bacter ia.