Empty egg cases of the common whelk are fairly frequent spongy finds amongst the detritus of the tide line beside my own Egg. The adult whelk is less evident, though I found the shell of the five year old below (if every spiral marks a year), not far from the type of sac it would have spawned from. Both are now part of a growing collection inside the Egg that helps to relate the life and times of my riverine parish.