Try posting it here:
www.ispot.org.uk/
Some knowledgable folk on there will give you an answer I expect. Could be any sort of invertebrate, may not be snail specific but maybe soil-living, and just happens to be on the snail. Well spotted though. Looks like your extension tubes have given you a very shallow depth of field, so makes the focussing difficult.
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Varmint, Sun 8 Jul 2012, 22:41,
Reply)
