Belemnites
Belemnites are an extinct group of cephalopod that probably looked like a squid.
Unlike nautiloids and ammonites, belemnites had a very solid internal skeleton called a rostrum. Many people will be familiar with belemnite rostra, they are straight, and look rather like bullets.
Apart from their shells, palaeontologists have also found some belemnite fossils that show their internal structure and soft parts. These fossils tell us a great deal about the way these animals lived. Belemnites had large eyes, and swam quickly using a form of jet propulsion. Like the octopus they could probably squirt clouds of black ink at their enemies to avoid attack.
Belemnite shells - rostra - are common fossils in some parts of Britain.
Belemnites first appeared about 360 million years ago. Along with ammonites and dinosaurs, they died out at the end of the Cretaceous period 65 million years ago.
