. Bulletin of the British Museum (Natural History), Geology. ARENIG IN SOUTH WALES 175 ft*, t. Fig. 52 Novakella copei sp. nov. a, holotype, axial shield, Llanfallteg Formation, loc. 50, early Llanvirn, D. artus Biozone, x 2, It. 15937; b, pygidium showing doublure, locality as Fig. 52a, x 2, ; c, latex cast from fragmentary cranidium, Llanfallteg Formation, loc. 52V, latest Arenig, Fennian, Dionide leviyena Biozone, x 2, It. 19637; d, small poorly preserved axial shield, Skiddaw Slates ofSkiddaw', original of Postlethwaite 1885: pi. 3, fig. 15, x 4, GSM 32833. broadly rounded outline
. Bulletin of the British Museum (Natural History), Geology. ARENIG IN SOUTH WALES 175 ft*, t. Fig. 52 Novakella copei sp. nov. a, holotype, axial shield, Llanfallteg Formation, loc. 50, early Llanvirn, D. artus Biozone, x 2, It. 15937; b, pygidium showing doublure, locality as Fig. 52a, x 2, ; c, latex cast from fragmentary cranidium, Llanfallteg Formation, loc. 52V, latest Arenig, Fennian, Dionide leviyena Biozone, x 2, It. 19637; d, small poorly preserved axial shield, Skiddaw Slates ofSkiddaw', original of Postlethwaite 1885: pi. 3, fig. 15, x 4, GSM 32833. broadly rounded outline of the front of the cranidium, which is almost semicircular. Maximum cranidial width is at its posterior margin and this just exceeds the sag. length. Axial furrows weakly denned posteriorly, such that the short, triangular postocular cheeks are hardly distin- guishable from the glabella. Three pairs of glabellar furrows of usual form for Novakella, with 2P longest and 3P most forward-inclined. Narrow, gutter-like palpebral rims extend backwards as far as the outer ends of 2P. Free cheeks not known. Six thoracic segments, pleurae widening progressively backwards. Articulation on first segment close to axial furrow and further removed therefrom on posterior segments. Pleural furrows distinctly defined, nearly reaching tips of pleurae. Pleural terminations are distinctly truncate. Pygidium broadly triangular, almost twice as wide as long. At least in the flattened preser- vation the border is not conspicuously flattened, but may have been more so in full relief. Four pairs of rather broad pleural furrows are defined, with indications of a weak fifth pair. Axis sharply conical, axial furrows including an angle of 40°-45°, and extending to two-thirds pygidial length; five (a faint sixth) axial rings are defined, which become progressively shorter (sag.) posteriorly; small terminal piece forms an almost equilateral triangle. Surface apparently lacking any Please note t
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