Fig. 9 in Morphological variations and geographic distribution of the rare Middle Jurassic ammonite Oecoptychius refractus

Fig. 9. Dimensional proportions of Oecoptychius refractus (Reinecke, 1818) [m]. The French and Polish specimens are compared with a reference point of the lectotype. A. Whorl height vs. shell diameter. B. Whorl thickness vs. shell diameter. C. Umbilicus vs. shell diameter. D. Whorl thickness vs. coiling ratio. For all given dimensional proportions, the French and Polish specimens form different groups.