Jurassic Ammonites (Stephanoceras) - Fresney, France
Here is a beautiful association of Middle Jurassic marine fossils collected from Fresney, France. Two Stephanoceras ammonites (3.2" and 2.3") are sitting near an unidentified bivalve fossil. The piece has been wonderfully prepared to create an 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.