Four large pieces, including two pumice stones (~10 and 15 cm) and two sponge branches ( also ~10 and 15 cm), one hiding a small brittle star.
Cite the IMLGS database as: Curators of Marine and Lacustrine Geological Samples Consortium. The Index to Marine and Lacustrine Geological Samples (IMLGS). National Geophysical Data Center, NOAA. doi:10.7289/V5H41PB8 [date of access].