The gliding motility of gregarine protozoans has intrigued biologists for several decades but more recently key roles for actin and myosin have been established. Using the trophozoites/gamonts of Gregarina cell surface translocation of added 2 μm occured with similar properties to those displayed by overt gregarine gliding including motility rates of between 0.1 and 10 μm/s. Although this movement has been viewed as a smooth process, gliding (and bead translocation) is an erratic process. Thus a single 2‐μm bead translocation observed over 30 s at 0.2‐s intervals demonstrated movement for only 26% of this time (39/150). At the low Reynolds Nos operating here bead movement can only occur when force is developed at the cell surface (no consideration of inertia could apply). A laser trap was used to position a bead at the cell surface. Subsequently, the cell surface motor was able to carry the bead posteriorly out of this force trap of 50 pN. Using established figures for myosin energetics we estimate that the number of myosin heads at the interaction site to be in excess of 200. Porospora gigantea demonstrated gliding/bead translocation rates of up to 60 μm/s=four times the speed of
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