An adult internal mould with some test, showing 5 whorls in which, instead of the normal planispiral serpenticone form, coiling is displaced sideways, so that one side of the specimen is flat with virtually no umbilicus, and the other is in the form of a broad cone rather like an amphitheatre. Sutures are visible including the last and the body chamber occupies just over half a whorl with the umbilical seam continuing for a further 1/4 whorl and showing uncoiling. On the flat side, part of the body chamber also shows an unusually flat area where a primary rib is partly absent from the whorl side. This appears to be attributable to predation rather than post- mortem damage. From Port Mulgrave, North Yorkshire.
Size: 51 mm in diameter.
Size: 51 mm in diameter.