A simple life!

The lot of the marine polychaete worm Arenicola marina is not altogether a happy one. He/she spends his/her life buried in the sand or mud, confined to a U shaped burrow, eating sand or mud, digesting what little nutrient it contains, and then crapping out the residue back onto the surface. The only fun that they have, is in creating a rather splendid cast from their sandy faeces, for the delectation of the passing blipper.

For some reason or other they always remind me of the old Mnemonic "On old Olympus' Towering Tops, a Finn and German viewed some hops"! Any guesses as to what objects the mnemonic refers to?