A fairly complete internal mould with half the body-chamber, developed on both sides with some test in the umbilicus. Part of the phragmocone is crushed on one side and the last suture is visible. A characteristic specimen from the Upper Spilsby Doggers, Donnington-on-Bain, Lincolnshire, England.
Size: 63 mm in diameter.
Size: 63 mm in diameter.