Tube-Worm Holes in Ringstead Chalk Boulders 8 – Detail of tube-worm burrows in a chalk beach boulder. The burrows are mostly unoccupied by the worms and mostly lack the mucus and sand-grain tube linings. Holes most probably made by Spionid polychaete worms of the Polydora genus. Photographed at Ringstead Bay in Dorset, England. Some of the burrows have been secondarily occupied by seashore creatures like barnacles.
Jessica's Nature Blog 