. Bulletin of the British Museum (Natural History) Geology Supplement. FOSSIL AND RECENT 71. soc epo Fig. 35. Protarpon priscus (Woodward). Neurocranium, dorsal view of the otic region. Based on Formation and locality. London Clay (Ypresian) of Sheppey, Kent, England. Description. Neurocranium. The skull roof is flat, marked only by two promi- nent ridges, which attain their greatest development at the sphenotic level. The mid-line of the skull roof is slightly depressed, an appearance which is enhanced by the presence of these ridges. A smaller specimen, , shows
. Bulletin of the British Museum (Natural History) Geology Supplement. FOSSIL AND RECENT 71. soc epo Fig. 35. Protarpon priscus (Woodward). Neurocranium, dorsal view of the otic region. Based on Formation and locality. London Clay (Ypresian) of Sheppey, Kent, England. Description. Neurocranium. The skull roof is flat, marked only by two promi- nent ridges, which attain their greatest development at the sphenotic level. The mid-line of the skull roof is slightly depressed, an appearance which is enhanced by the presence of these ridges. A smaller specimen, , shows weak ridges. By analogy with Tarpon and Megalops these ridges contained the supra- orbital sensory canals. The supraorbital sensory canal is known to pass posteriorly into the parietal bones in Megalops and Tarpon and a similar situation existed here as evidenced by the pores upon the parietal bones illustrated. In the otic region the roof is parallel-sided, but posteriorly it is produced into three processes ; a median supraoccipital with large epiotic processes on either side. Each frontal has a square posterior margin and in consequence imparts an ' L '- shape to the adjacent pterotic. The medially united parietals are slightly longer than broad and have a sinuous suture with both pterotics and frontals. The lateral ethmoid is similar to that of Tarpon. In posterior view the pentagonal supraoccipital bears a prominent supraoccipital crest, on either side of which is a slight depression. The epiotic also exhibits a faint depression immediately beneath the epiotic process. This depression is continued upon the exoccipital. The exoccipital is large and meets its fellow of the opposite side above and below the foramen magnum. Laterally the exoccipital forms the. 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
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