Figure 1

The eversible vesicles of S. viridis. (A) Schematic drawing of the adult in ventral view, showing the eversible vesicles out of the ventral tube. (a) Distal part of the eversible vesicle; (b) basal part of the eversible vesicle; (c) ventral tube; (d) furca; (B) lateral view of the adult, with the eversible vesicles extracted from the ventral tube. Scale bars = 0.05 mm.