. Bulletin of the British Museum (Natural History), Geology. 3io REVISION OF ACTINOPTE R YGI AN AND COELACANTH FISHES Further, two isolated prootics of Lepidotes latifrons ( P 9998) from the Oxford Clay at Peterborough have been cleaned up in acid, and confirmation of all the existing foramina in the prootic of Lepidotes mantelli obtained. Description. Neurocranium. This is well ossified. All the bones constituting the neurocranium are stout and cancerous, together forming a much more solid and heavy brain-case than in Lepidotes semiserratus (Rayner, 1948 : 305). The large prootics whi
. Bulletin of the British Museum (Natural History), Geology. 3io REVISION OF ACTINOPTE R YGI AN AND COELACANTH FISHES Further, two isolated prootics of Lepidotes latifrons ( P 9998) from the Oxford Clay at Peterborough have been cleaned up in acid, and confirmation of all the existing foramina in the prootic of Lepidotes mantelli obtained. Description. Neurocranium. This is well ossified. All the bones constituting the neurocranium are stout and cancerous, together forming a much more solid and heavy brain-case than in Lepidotes semiserratus (Rayner, 1948 : 305). The large prootics which have grown back over the lateral and basioccipitals have eliminated most of the cartilaginous interspaces seen in earlier species. The epiotics are large and meet in the mid-line. Posteriorly they present a triangular appearance forming over half of the depth of the occiput, and there is no supra- occipital. Beneath the epiotics lie the even larger lateral occipitals which, meeting in. \ .-â Bsph psph \ bpt pr i tttt r>' u K Psph 24mm Fig. 44. Lepidotes mantelli Agassiz. Neurocranium in lateral view, slightly diagrammatic. From Leicester Museum 5, 1957. the mid-line, extend ventrally to form the upper rim of the foramen magnum. The lateral occipitals extend a considerable distance on to the lateral wall of the neuro- cranium, completely surrounding the foramen for the vagal nerve (Text-fig. 44). Dorsally abutting on the lateral occipital and not quite reaching the anterior edge of the epiotic is a small intercalar (opisthotic of Woodward, 1916, pi. 10, fig. 1). Beneath the lateral occipital is a massive basioccipital which is capped posteriorly by a pair of neural arches. The basioccipital is distinctly grooved below for the basi- cranial canal. The prootic is another large element which posteriorly meets both the basioccipital and the lateral occipital, but which is separated from the intercalar by a cartilaginous interspace. Dorsally there is a narro
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