Spisula hartingi nov. spec., a new bivalve from the Eemian in the Netherlands

While collecting shells from the sand used for draining large areas on the western side of Amsterdam, members of the Amsterdam branch of the Netherlands Malacological Society found some valves of a hitherto unknown species of Spisula. This sand is brought up by a dredger from a depth of 20 to 30 m below O.D. in the “Slotermeer”, a small lake near the drained area. The deposits from which these shells are presumably derived belong to the Eemian (last interglacial) stage and have a littoral facies, being rich in marine shells. No right valves have been found, so that the following description is of the left valve of the species.