Some Kind of Jellyfish
5 m Depth.
Possibly 10-tentacled burrowing anemone? 10 tentacles, between small rocks at bottom of tidepool. See alternate photo for stalk.
I think this is a Leathery Anemone
Cnidaria (/naɪˈdɛəriə/ with a silent c) is a phylum containing over 10,000species of animals found exclusively in aquatic and mostly marine environments. Their distinguishing feature is cnidocytes, specialized cells that they use mainly for capturing prey. Their bodies consist of mesoglea, a non-living jelly-like substance, sandwiched between two layers of epithelium that are mostly one cell thick. They have two basic body forms: swimming medusae and sessile polyps, both of which are radially symmetrical with mouths...