Fig. 2

Comparison of selected [m] and [M] morphotypes of Peltoceras athleta: A Peltoceras athleta [M]; B Peltoceras athleta annulosum [m], C Peltoceras athleta pseudotorosum [m], and the six (i to vi) ornamental stages defined by Bonnot [25]. All specimens from the Montreuil-Bellay area (PYB collection). Black dots indicate the end of the phragmocone. Scale bar is 10 mm