Jurassic Ammonites (Stephanoceras) - Fresney, France
Here is a beautiful association of Middle Jurassic marine fossils, collected from Fresney, France. There are two Stephanoceras ammonites (3.2" and 1.75") that are next to a bivalve fossil and a small unidentified ammonite. The piece has been wonderfully prepared to create this aesthetic display.
Ammonites were predatory mollusks that resembled a squid with a shell. These cephalopods had eyes, tentacles, and spiral shells. They are more closely related to a living octopus, though the shells resemble that of a nautilus. True ammonites appeared in the fossil record about 240 million years ago. The last lineages disappeared 65 million years ago at the end of the Cretaceous.