Heteromorph Ammonites Collection
These are Heteromorph Ancyloceras (Audiloceras) ammonite. They has what is known as a heteromorph shape. While most ammonites have spiral shells that retain the same shape throughout growth homeomorph), a major group of ammonites, the Ancyloceratina, emerged during the Late Jurassic that had uncoiled shells and was called heteromorph ammonites (different-shaped).