Stones With Holes at Charmouth Beach 18 – Beach stone with holes made by marine invertebrates at Charmouth, Dorset, England. The larger holes are made by boring bivalve molluscs and the smaller holes by marine polychaete tube worms. The larger holes may have been created by the Wrinkled Rock Borer Hiatella arctica. The shell remaining in the burrow could be Hiatella or maybe the burrow has been secondarily occupied by Irus irus.
Jessica's Nature Blog 