Helicoprion, whorl-tooth shark Dimorphodon ‭ ‬and then ground by

‭ ‬and then ground by the teeth at the back

Sloth Claw

Cleveland-Lloyd Quarry

The specimen represented here is a female

This dwarf mammoth tooth shows the ridges of enamel cemented by dentine

Helicoprion, whorl-tooth shark Dimorphodon ‭ ‬and then ground byHelicoprion ("Spiral Saw") was a long lived genus of shark like cartilaginous fish that first arose in the oceans of the late Carboniferous 280 million years ago, survived the Permian Triassic Extinction Event, and eventually went extinct during the early Triassic some 225 million years ago. The only fossils known are the teeth, which were arranged in a fantastic "tooth whorl" strongly reminiscent of a circular saw. It was not until the discovery of