. Bulletin of the British Museum (Natural History), Geology. CRETACEOUS FISHES FROM THE LEBANON 87 B. Fig. 6. The left upper jaw in lateral view of Ctenothrissiformes (left) and Berycoidei (right). A. Ctenothrissa radians (Agassiz), Ctenothrissidae, Upper Cenomanian, England, xi'5- B. Aulolepis typus Agassiz, Aulolepidae, Upper Cenomanian, England, X2. C. Macristium chavesi Tate Regan, Macristiidae (? Ctenothrissiformes) Extant, Atlantic, X27. After Marshall, 1961. D. Gnathoberyx stigmosus gen. et sp nov., Trachichthyidae, Upper Senonian, Sahel Alma, Lebanon, x 8. E. Hoplopteryx macrac
. Bulletin of the British Museum (Natural History), Geology. CRETACEOUS FISHES FROM THE LEBANON 87 B. Fig. 6. The left upper jaw in lateral view of Ctenothrissiformes (left) and Berycoidei (right). A. Ctenothrissa radians (Agassiz), Ctenothrissidae, Upper Cenomanian, England, xi'5- B. Aulolepis typus Agassiz, Aulolepidae, Upper Cenomanian, England, X2. C. Macristium chavesi Tate Regan, Macristiidae (? Ctenothrissiformes) Extant, Atlantic, X27. After Marshall, 1961. D. Gnathoberyx stigmosus gen. et sp nov., Trachichthyidae, Upper Senonian, Sahel Alma, Lebanon, x 8. E. Hoplopteryx macracanthus Patterson, Trachichthyidae, Senonian, England, Xi-5- F. Myri- pristis murdjan Forskael, Holocentridae, Extant, Red Sea, xi-6. of the evidence that the Ctenothrissiformes lie closer than any other group to the ancestry of the Beryciformes (Patterson, 1964 : 463-466 ; Greenwood et al., 1966 : 369) they must be carefully considered. There can be little doubt that the maxillary dentition of Gnathoberyx is primitive, not secondary. In Hoplopteryx macracanthus and Myripristis there is every reason to believe that this is true (Patterson, 1964 : 440), and the argument receives added force from the well-toothed maxilla of Gnathoberyx. But it is possible that the upper jaw of Gnathoberyx is specialized, for whatever purpose, by reduction in the ascending process of the premaxilla and elongation of the toothed part of the maxilla, secondarily producing a ctenothrissif orm type of jaw from a more typical berycoid one. Some support for this hypothesis may be found in the relatively late age of Gnathoberyx (U. Senonian compared with the first trachichthyids in the L. Cenomanian) and in the generally specialized aspect of the fish—abundant spiny ornament, enlarged lateral line and ventral ridge scales, the short gape, reduced or lost supramaxillae and large marginal teeth in the upper jaw. And in one respect, the presence of a well developed postmaxillary process on the premaxi
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