Laboratory growth rates of six species of freshwater Gymnamoebia.

Laboratory growth rates of six species of Gymnamoebia, isolated from English chalk streams and cultured on bacteria, have been determined at four different temperatures. Generation times ranged from 4.46 to 33.3 h. A linear relationship between log10 specific growth rate and the reciprocal of the absolute temperature was demonstrated for four species. A significant regression of log10 generation time on log10 cell volume was obtained for data on amoebae in combination with data on ciliates taken from the literature. This regression may be used to predict the growth rates of other species of amoebae and ciliates of known cell volume.