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Keywords from Image Description:
The Quarterly journal of the Geological Society of London . PROCEEDINGS OF THE GEOLOGICAL SOCIETY Mar Pupa anglica Vertigo substriata Vertigo palustris Clausilia bidens pusilla nigricans edentula Rolphii pygmsea Achatina acicula angustior Carychium minimum alpestris Acme fusca and var reversed Freshwater Shells Succinea putris