. Bulletin of the British Museum (Natural History), Geology. 84 CRETACEOUS FISHES FROM THE LEBANON. Fig. 5. Gnathoberyx stigmosus gen. et sp. nov. Left upper jaw. Below, in lateral view ; above, the anterior part of the jaw in medial view. x 12 approx. (Text-fig. 6b). On the outer face of the toothed part of the maxilla there is a groove, overhung by a flange anteriorly, which closely resembles the groove in Ctenothrissa which I (Patterson, 1964 : 232 ; Text-fig. 6a) interpreted as housing a ligament attaching the upper jaw to the mandible. The hind end of the maxilla is not completely preserv
. Bulletin of the British Museum (Natural History), Geology. 84 CRETACEOUS FISHES FROM THE LEBANON. Fig. 5. Gnathoberyx stigmosus gen. et sp. nov. Left upper jaw. Below, in lateral view ; above, the anterior part of the jaw in medial view. x 12 approx. (Text-fig. 6b). On the outer face of the toothed part of the maxilla there is a groove, overhung by a flange anteriorly, which closely resembles the groove in Ctenothrissa which I (Patterson, 1964 : 232 ; Text-fig. 6a) interpreted as housing a ligament attaching the upper jaw to the mandible. The hind end of the maxilla is not completely preserved in either specimen : the bone evidently became much thinner and was without teeth. The dorsal edge of the toothed part of the maxilla is thin and smooth so far as it is preserved, and in neither specimen is there any trace of supra- maxillae : if these were present they must have been small and flimsy, not like the large supramaxillae of Ctenothrissiformes and most Berycoidei. In contrast to most of the superficial bones of the head, the upper jaw is smooth and without ornament. The head of the quadrate lies almost below the centre of the orbit, and the mandible is rather short. The ventral edge of the dentary and the flange overhanging the groove for the sensory canal on both the dentary and articular are produced into large, closely packed, recurved spines. In size and shape these spines resemble the large marginal teeth of the upper jaw, but differ from them in having no pulp cavity. The oral border of the dentary bears small, clustered teeth, apparently with a single large procumbent tooth at the symphysis. Whether the mandibular sensory canal ran in a closed tube or in an open groove cannot be seen. Opercular bones. The preopercular is typically trachichthyid, but because of the forward position of the suspensorium the ventral limb is about half as long as the dorsal and the angle in the bone is acute, almost 900. The bone is broad throughout its length and, as usual in
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