. Bulletin of the British Museum (Natural History) Geology Supplement. 42 UPPER CRETACEOUS TELEOSTS the dorso-medial regions of each palatine thus providing an articulatory facet for those bones. The vomer is large and wide although extremely shallow. Anteriorly it tapers to a point and is attached to the underside of the extreme anterior end of the meseth- moid. The vomer widens posteriorly and its edges are in close association with longitudinal ventro-medial facets on the palatines. More posteriorly below the lateral ethmoids the vomer tapers and merges into the parasphenoid. The vomer is s
. Bulletin of the British Museum (Natural History) Geology Supplement. 42 UPPER CRETACEOUS TELEOSTS the dorso-medial regions of each palatine thus providing an articulatory facet for those bones. The vomer is large and wide although extremely shallow. Anteriorly it tapers to a point and is attached to the underside of the extreme anterior end of the meseth- moid. The vomer widens posteriorly and its edges are in close association with longitudinal ventro-medial facets on the palatines. More posteriorly below the lateral ethmoids the vomer tapers and merges into the parasphenoid. The vomer is spo. Fig. i8. Cimolichthys levesiensis Leidy. Neurocranium in lateral view. The inset shows a diagrammatic representation of the prootic in antero-lateral view. From number toothed in its anterior region, and the teeth are in a median row, there being four teeth in all. The bases of the teeth are clearly observable although none of the teeth were present on the specimen examined. The lateral ethmoids are poorly ossified bones, especially medially. Each is com- posed of thin sheets of bone which represent superficial ossifications of cartilaginous blocks. Dorsally, each lateral ethmoid is attached to the underside of the frontals, and ventrally the only well ossified part of the bone occurs. This is represented by a small crenulated knob, in life capped by cartilage, which articulates with a definite area at the posterior end of the dorsal region of each palatine. The parasphenoid is long and bent through a shallow angle at the base of the ascending process. The anterior region of the bone is flattened and expanded where it contacts the vomer. The parasphenoid narrows below the orbit and attains its minimum width at the base of the ascending process. The ascending process passes dorsally and contacts the prootic. The foramen through which the internal carotid artery passed into the base of the orbit lies in the ventral region of the ascend- ing process. Below thi
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