Hildoceras bifrons (Bruguière).
Split beach nodule. Inside the 3D Ammonite is preserved in golden pyrite. Outer whorl terminates in a collapsed section. The characteristic central' canal' is shown to perfection on this zonal index Ammonite.
Jurassic, Upper Toarcian, Bifrons Zone.
Port Mulgrave, Yorkshire.
Ammonite : 5.3 cm diam.
