Exteriors worn; identification confirmed by interior of shell and animal with green mantle, peripheral pallial tentacles and lack of inwardly oriented repugnatory glands.
These images are the furthest south on the British coast of the North Sea seen for this inquiry. It may yet be found further south on the Scottish coast and perhaps in the extreme north of England; shore work and visible evidence are needed.

APPENDIX re range advance/retreat: flic.kr/p/2jW74ig

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