FIG. 6. — Promesacanthus eppleri n. gen., n in Promesacanthus eppleri n. gen., n. sp., a mesacanthid (Acanthodii, Acanthodiformes) from the Lower Devonian of northern Canada

FIG. 6. — Promesacanthus eppleri n. gen., n. sp.: A, photograph of enlarged scales around the origin of the dorsal fin spine of UALVP 42652; B, dorsal fin of UALVP 42652 showing aligned scales and fin spine ornament; C, dorsal fin spine base of UALVP 41672 its associated basal plate; D, dorsal midline of the caudal peduncle of UALVP 42652; E, scales near the tip of the caudal fin axis of UALVP 41672; F, scales of the hypochordal lobe of the caudal fin of UALVP 41672. Scale bars: A, C­F, 1 mm; B, 5 mm.