The Flagellar Apparatus Ofhymenomonas Coronata(prymnesiophyta)1

The ultrastructure ofHymenomonas coronataMills was reinvestigated to determine the microarchitecture of the flagellar apparatus. Cell morphology and flagellar apparatus structure are very similar to those ofPleurochrysis.Some important variations occur. First, a crystalline root (= compound root) is absent on microtubular root 1. Second, a two‐stranded microtubular root emanates at a right angle from microtubular root 2. Third, a fibrous root emanates from the dorsal region between the basal bodies and extends to the cell's right, paralleling microtubular root 3. These similarities and variations in flagellar apparatus characters are discussed in reference to known variations in the Prymnesiophyta.