Fig. 4.

Population development of the ciliate Bromeliothrix metopoides fed with small and large forms of the flagellate Polytomella sp. in three different treatments (A–C, D–F, G–I); the treatments differed in prey concentration and the relative contribution of the two flagellate morphotypes. Panels A, D and G show the abundance of the two flagellate forms; graphs B, E and H show cell numbers of the ciliate with its two different sizes (microstomes and macrostomes). The bottom panels (C, F and I) report the occurrence of macrostomes as percentage of the total ciliate abundance.