Alex Mustard / Grey bonnet snail (Phalium glaucum) female laying a large mass of orange eggs. This egg mass has been laid by several snails. Bitung, North Sulawesi, Indonesia. Lembeh Strait, Molucca Sea.

Georgette Douwma / Grey bonnet snail (Phalium glaucum). Ambon, Indonesia.

Juergen Freund / Bonnet snail (Phalium sp) Lembeh Strait, North Sulawesi, Indonesia.

GEORGETTE DOUWMA / Red emperor fish / snapper (Lutjanus sebae) feeding on a Grey bonnet (Phalium glaucum). Lembeh Strait, North Sulawesi, Indonesia.

Juergen Freund / Photograph and X-ray of shell of the Scotch Bonnet {Phalium granulatum} Note: the x-ray shows the shape of a hermit crab which has inhabited the shell's inner section.

Juergen Freund / X-ray of the shell of the Scotch Bonnet {Phalium granulatum} showing outline of Hermit crab which has inhabited the shells inner section.

Juergen Freund / Shell of the Scotch Bonnet {Phalium granulatum}

Juergen Freund / Bonnet (Helmet) snail shell {Phalium granulatum} Atlantic Ocean

GEORGETTE DOUWMA / Grey bonnet / Helmet shell (Phalium glaucum). Lembeh Strait, North Sulawesi, Indonesia

GEORGETTE DOUWMA / Red hermit crab (Dardanus megistos) using a Grey bonnet / helmet shell (Phalium glaucum) as a home. Lembeh Strait, North Sulawesi, Indonesia

GEORGETTE DOUWMA / Red hermit crab (Dardanus megistos) using a Grey bonnet / helmet shell (Phalium glaucum) as a home. Lembeh Strait, North Sulawesi, Indonesia

Franco Banfi / Sea anemone (Calliactis parasitica) usually associated with hermit crabs, here on a Mediterranean bonnet shell (Semicassis granulata), Ponza island, Italy, Tyrrhenian Sea, Mediterranean.