Channeled Top Snail (Calliostoma canaliculatum), photographed along the Bodega Bay shoreline on 23 November 2015.
Here's a view from the side as the snail was crawling. The tentacles and a small dark eye are visible on the right side. You can also see the foot — speckled, with a fuzzy-looking texture. And if you look closely, there's a partial view of the operculum ("trap door") — golden and circular (although only half is in view below the back edge of the shell).
Here's one more view — from below, when the snail was trying to right itself.
What a pretty foot! And a beautiful snail. I love the iridescence along the spirals.