This 24mm Topshell was caught in the upper part of a granitic bank, SW. of Petit Bé.
Shallow water specimens are rare, and often bear glorious colours.

Like many Sea Slugs, Calliostoma zizyphinum feeds on Hydroids.
Purple specimens are more commonly encountered in shallow water, while brownish ones live deeper.
This might be linked with diet variations.

Nucella lapillus (Linnæus, 1758). 23mm, 25mm.
More abundant on intertidal rocks, it becomes rare in sublittoral waters.
Feeds on Mussels, Worms, and even other Dogwhelks.
This colour is uncommon. Usual specimens are white, with ugly encrustations.

This variable species offers all kind of colours, even in the aperture.
A very nice piece is be the pure white shell, smooth, with a golden mouth. Not easy to find.
Specimens with intact protoconch can be found in sheltered areas.