Fig. 4From: Ordovician–Silurian Lilliput crinoids during the end-Ordovician biotic crisisBootstrapping results comparing the 95% confidence intervals for a given formation to the mean of the observed calyx volumes from a subjacent or superjacent formation indicatged with an arrow. (V Vauréal Formation, E Ellis Bay Formation, B Becscie Formation, J Jupiter Formation)Back to article page