The Museum Collection: Mollusc Shells
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Bradford on Avon Museum has to be selective about objects of natural history that are added to the collection. This is because of the difficulties in preserving organic material.
This restricts the collection to just mollusc shells and some skeletal material and teeth of vertebrate animals. However, the Museum is keen to build up a collection of photographs of local animals, plants and natural environments.
Click on the thumbnail pictures for a bigger view.
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Freshwater bivalve mollusc shells
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Anodonta sp.
A pair of swan mussel shells from the river Avon at Barton Bridge, Bradford. These are animals that live in tranquil water, but their shells are cast up when the quiet backwaters of the Avon are disturbed during periods of flooding.
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Sphaerium corneum (Linnaeus, 1758)
Two shells of the freshwater bivalve mollusc known as an orb mussel, found on the bank of the River Avon on the Winsley side near Stokeford Bridge. The smaller one retains its chitinous outer covering.
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Freshwater gastropod (snail) shells
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Planorbis planorbis Linnaeus, 1758
Two examples of the ram’s horn snail which were excavated from the River Avon by dredging to improve water flow during the flooding at Christmas 2013. The thin shell is almost coiled along one plane.
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Viviparus viviparus Linnaeus, 1758
The banded shells of the common river snail are thick and grow into a spire. The heavy shell suggests the ability of this snail to exist where the river currents are greater.
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Radix auricularia (Linnaeus, 1758)
The ear pond snail shell has a large opening or aperture, which gives both its common and Latin names. It is tolerant of very poor-quality environments in lakes and rivers.
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Land gastropod shells
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.Pomatias elegans (Müller, 1774)
The round-mouthed snail is not common in Britain because its range is mostly in southern Europe. It is not related to the other snails in the garden, but to the familiar winkles of rocky seashores. The small sturdy ribbed shell is sometimes found in crumbly soil in woods or hedges.
Clausilia bidentata (Ström, 1765)
The tiny shells of the door snail are often overlooked. The animals are often found on, or more frequently under, stones.
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