Figure 3.

Both T. majus and Uronemella anchor to a surface with a mucous stalk (red line) and they exert a force on the fluid to generate a flow. Blue arrows show the stream lines of water as it is pulled past the cell. These stream lines were reconstructed from the motion of tracer particles around the cell, as previously described [19]. The vortex to either side of the cell is generated by the back flow from the nearby cover slip [20,21]. (a) Thiovulum majus generates a flow by rotating flagella. (b) Uronemella generates the flow by synchronously beating its cilia. Scale bars, (a,b) 10 μm.