fossil, [301];
commensal with Polynoid, [298];
colour, [292]
nerve cords, [255];
gills, [261];
operculum, [261];
cirri, [265];
fossil, [301];
commensal with Polynoid, [298];
colour, [292]
nerve cords, [255];
gills, [261];
operculum, [261];
cirri, [265];