. Bulletin of the British Museum (Natural History), Geology. 124 R. A. FORTEY & R. M. OWENS Other occurrences. S. (C.) crossi has only been found in the Pontyfenni Formation of south Wales, biozone of Bergamia rushtoni. It is known otherwise from west of Banc-y-felin, at Rushmoor (Survey loc. 38SW EA5), at Bron-y-Gaer (Survey loc. 38SW E/l), and at Sarn-las (loc. 48). Diagnosis. Shumardia (Conophrys) with broad (tr.) anterior glabellar lobe, which is hardly pointed and defined by faint preglabellar furrows; bacculae present in axial furrows. Six tho- racic segments, no macropleural segment
. Bulletin of the British Museum (Natural History), Geology. 124 R. A. FORTEY & R. M. OWENS Other occurrences. S. (C.) crossi has only been found in the Pontyfenni Formation of south Wales, biozone of Bergamia rushtoni. It is known otherwise from west of Banc-y-felin, at Rushmoor (Survey loc. 38SW EA5), at Bron-y-Gaer (Survey loc. 38SW E/l), and at Sarn-las (loc. 48). Diagnosis. Shumardia (Conophrys) with broad (tr.) anterior glabellar lobe, which is hardly pointed and defined by faint preglabellar furrows; bacculae present in axial furrows. Six tho- racic segments, no macropleural segment. Pygidial axis exceptionally broad for subgenus, occupying half pygidial width at first ring. Description. The holotype (Figs 19a-c) is almost undistorted and shows the original convexity. Exoskeleton almost twice as long as wide. This specimen demonstrates that the glabella was turned down with the cephalic edge, but still terminates inside the margin. Other cranidia are all slightly crushed. That in Fig. 19h apparently shows the glabella continuing to the margin as a tongue in the manner of Kweichowilla (right side), but this is an artefact of preservation. Glabella occupies just under half cranidial width at occipital ring. Axial furrows are deep posteriorly but shallow abruptly around the anterior glabellar lobe, so that they appear effaced on the more poorly preserved material; the course of the preglabellar furrows can be discerned on internal moulds (Fig. 19d). There are distinct bacculae which constrict the base of the glabella a little. The anterolateral glabellar lobes protrude outwards, but not far beyond the level of the lateral margins of the occipital ring; the furrows defining them are narrow and do not extend more than one-third across the median glabellar lobe. On flattened cranidia the position of the anterolateral lobes is displaced relatively backwards because of the splaying out. Fig. 19 Shumardia (Conophrys) crossi sp. nov. Upper Arenig, Fennian (Bergamia
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