Bardin, JérémieRouget, IsabelleCecca, Fabrizio2013FIG. 3 in Late Pliensbachian (Early Jurassic) ammonites from Lac de Charmes (Haute-Marne, France): Systematic, biostratigraphy and palaeobiogeography10.5281/zenodo.5379563FIG. 3. — Abbreviations of the dimensional parameters used in the systematic descriptions: D, shell diameter; h, whorl height starting from the umbilical seam to the beginning of the forward projection of the rib; Ph, phragmocone diameter; U, umbilicus diameter; Wh, whorl height; Wb, whorl breadth.PhhUWhWbD