. Bulletin of the British Museum (Natural History), Geology. BRITISH WEALDEN SHARKS 295. 2 mm Fig. 5. Hyhodus ensis Smith Woodward. Tooth in labial (a) and medial (b) view. 2693, Grinstead Clay ; Tilgate Forest, Sussex. tend towards H. basanus in having a more slender central cusp with rather coarse striae covering almost half of the labial face, but they have only two pairs of lateral cusps : 26024 is particularly like the typical Weald Clay H. basanus, but it seems probable that it is not an early example of this species but a tooth of H. ensis in which the evident trend towards narrowing of
. Bulletin of the British Museum (Natural History), Geology. BRITISH WEALDEN SHARKS 295. 2 mm Fig. 5. Hyhodus ensis Smith Woodward. Tooth in labial (a) and medial (b) view. 2693, Grinstead Clay ; Tilgate Forest, Sussex. tend towards H. basanus in having a more slender central cusp with rather coarse striae covering almost half of the labial face, but they have only two pairs of lateral cusps : 26024 is particularly like the typical Weald Clay H. basanus, but it seems probable that it is not an early example of this species but a tooth of H. ensis in which the evident trend towards narrowing of the central cusp and extension and coarsening of the ornament has gone farther than in other examples. Among the new material from the Cliff End and Paddockhurst bone-beds there are no complete large teeth, but isolated central cusps and imperfect crowns are very common. All of these large teeth can be referred to H. ensis : they show a range in breadth of the central cusp from stout forms like the Purbeck H. ensis to slender forms approaching the proportions of H. basanus, but the striae on the labial face are always short, fine and closely packed, and on the lingual face they are always shorter than in H. basanus and are longer at the margins of the central cusp than in the centre. No examples of H. ensis are known from horizons above the Grinstead Clay. Affinities. H. ensis is a species which ranges from the Middle Purbeck to the Grinstead Clay (Paddockhurst bone-bed and Tilgate Forest). In the Wealden the teeth show a trend towards narrowing of the central cusp, sometimes accompanied by coarsening and lengthening of the striae which may produce teeth closely similar to those of H. basanus in Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original British Museum (Natural History). London : BM(NH)
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