Pyramidellid sp. (protoconch)

Fossil mollusc, Pyramidellid sp (protoconch) (gastropod); good images of development of heterostrphic involute apex. borehole from the Quaternary (Pleistocene, Early Pleistocene) deposits, Icenian Crag, of the Royal Society Borehole, Ludham, Norfolk, England examined by Dr Peter E.P. Norton, 1961