Dear David, We always seem to find our most common Calliostoma zizyphinum
(Linné,1758)on seaweed or on the edge of rocks with attachments. Sponges
would seem to be a readily available source of food and I have been told
this has been confirmed by some Italian workers.
Unfortunately I do not have a reference to their paper/s
Stanley Francis.
Belfast, Northern Ireland. U.K.
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