Fig. 4. A in Taxonomic notes on "Phoebodus heslerorum" and Symmorium reniforme (Chondrichthyes, Elasmobranchii).

Fig. 4. A. "Ctenacanthus" costellatus Traquair, 1884, fragment of specimen NHM−P20144−5 from Eskdale, Dumphrieshire, Scotland, Lower Carboniferous; a group of teeth. B. Cladoselache clarki (Claypole, 1893), fragment of specimen NHM−P 9272 from Berea, Ohio, late Famennian, Cleveland Shale; two tooth families in occlusal−labial views. Scale bars 5 mm. Coated with ammonium chloride for better contrast.