is it zebra mussel towards centre right
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Its freshwater not saltwater.
Yes Tony, it is certainly not periwinkle either plant or animal!
It no longer shows up on the collection for Vinca.
http://www.ruthenica.com/documents/Continental_Russian_molluscs_ver1-0 page 12
The other could well be a zebra mussel (listed page 253 on)
Thanks for the links, looks like I should have collected some to sell according to that http://www.conchology.be/ website!
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