Fig. 30 in Early-Middle Ordovician cephalopods from Ny Friesland, Spitsbergen - a pelagic fauna with Laurentian affinities

Fig. 30. Diagrams of relative angle of expansion, relative chamber length, and relative siphuncular diameter of Bactroceras fluvii sp. nov., uppermost Olenidsletta Member, V3 trilobite zone, Dapingian, adjacent to Hinlopenstretet, Ny Friesland, Spitsbergen. See Supp. file 1 for details of measurements.