Table 2 in The coiled Middle Ordovician cephalopod genera Trocholites and Curtoceras (Tarphyceratida) from Baltoscandia and north-central Europe

Table 2. Parameters and ratios used for the description of the tarphyceratid specimens studied herein.
Parameter [unit]Abbrev.Calculationconch diameter [mm]dm–whorl height [mm]wh–whorl width [mm]ww–umbilical width [mm]uwdm1−wh1−wh2apertural height [mm]ahdm1−dm2imprint zone [mm]izwh 1 −ahwhorl expansion rate (outline)WERdm(dm / dm)2 1 2whorl expansion rate (apertural height)WERah[dm / (dm −ah)]2 1 1imprint zone rateIZRiz / whumbilical width indexUWIuw / dmconch width indexCWIww / dmwhorl width indexWWIww / wh