Figure 21: Bipartitor and pseudoumbilicus in Eponides repandus (
A: dorsal (spiral) view, B: lateral view of dissected specimen. C: oblique umbilical view of dissected specimen. D: detail of rotated oblique umbilical view.
bi: bipartitor; c: spiral umbilical canal; f: foramen; pu: pseudoumbilicus; sf: septal face: note supplementary apertures closed by septal flap covering the septal face; up: umbilical plate.