Since Sept. 25, 1925, for a period of twenty months, Councilmania dissimilis has been grown in Professor Kofoid's laboratory in mixed cultures with bacteria in various kinds of mediums mentioned. It grows abundantly in carefully made mediums at a constant temperature of 37.5 C.; however, the abundance varies with the different strains and even with the same strain. This would be expected, since the bacterial flora is never the same for any two strains, and in the cultures of the same strain there is variation of growth of the bacteria because the different kinds of organisms present vary as to the time of their separate lag periods; these, in turn, affect the lag period of the ameba.
From the stools of six patients, ten separate strains of Councilmania dissimilis Kofoid have been obtained in cultures in the Protozoological Laboratory of the University of California.
Councilmania dissimilis continues to