I saw several of these anemones with their bodies buried in sand.
Possibly 10-tentacled burrowing anemone? 10 tentacles, between small rocks at bottom of tidepool. See alternate photo for stalk.
To the left of the white-tentacled anemone - hard to see (hence crypta), with 12 tentacles.
Found in rocky intertidal. Photo scanned from 35mm slide.
In the sand, western side of the harbor. Column more than 5 mm in diameter, I think, though hard to tell in the water. That size plus the 12 tentacles should make it H. crypta.