Ammonite

I bought this particular ammonite in the fossil shop in Lyme Regis where it had been hammered out of the rocks by a local collector.
Ammonites are probably the best known of all fossils, because of their ribbed spiral shells. These creatures lived in the seas between 240 - 65 million years ago when they became extinct along with the dinosaurs. The name 'ammonite' comes from the Greek ram-horned god called Ammon. Ammonites belong to a group of predators known as cephalopods, which includes their living relatives the octopus, squid, cuttlefish and nautilus.