I 



SUB-CLASS V 



GANOIDEI 



83 



served in the Lithographie Stone (Upper Jurassic) of Germany and France. 

 L. 7)ia7iteUi, Ag., from Wealden. Also Jurassic of India and Siberia, and 

 Cretaceous of Brazil. 



Family 3. Eugnathidae. Woodward. 



Trunk slender, covered with rhomboid enamelled scales. Marginal teeth conical. 

 Cranial and facial bones moderately robust, externally enamelled, and opercular 

 apparatus complete. Snout not produced. Fin-rays robust, fulcra conspicuous. 

 Dorsal fin short and acuminate. Vertebral column rarely more than incomplete 

 rings. Tail externally homocercal or hemi-heterocercal. Trias to Cretaceous. 



Eugnathus, Ag. {Heterolepidotus, Egerton). Cleft of mouth wide, with large, 

 conical, pointed laniary teeth and numerous smaller pointed teeth between 

 these. Head and opercular bones smooth or tuberculated. Fins powerful, 

 the dorsal arising opposite the pelvic pair, stouter and longer than the anal 

 fin; caudal fin forked, externally hemi-heterocercal. Scales rather thick, 

 mostly longer than deep, and with serrated hinder border. The type species, 

 E. orthostomus, Ag., a slender fish, common in the Lower Lias of Lyme Regis, 

 Dorset. Other species in the Lias, and ranging upwards to the Lithographie 

 Stone {E. microlepidotus, Ag.) and Purbeck Beds. 



Caturus, Ag. ( Uraeus, Ag.), (Fig. 149). Essentially identical with Eugnathus, 

 but scales thinner, more deeply overlapping, and less narrowed near the ventral 



Fig. 149. 

 Cahorus elongatus, Ag. Upper Jurassic (Lithograpliic Stone) ; Ceriii, Aiu, France. V-> »at. size. 



border of the fish. Endoskeleton of trunk usually well displayed in the fossils, 

 showing hemi-vertebrae, short ribs, and free neural spines in the abdominal 

 region. Ranging from the Trias to the Upper Jurassic, espeeially fine speei- 

 mens being known from the Lower Lias of England (C. heterurus, Ag. sp., etc.), 

 and the Lithographie Stone of France, Bavaria, and Würtemberg {C. furcatus, 

 elongatus, maxi7nus, Ag., etc.). 



Strobilodus, Wagner ; Ditaxiodus, Owen. Large fishes resembling Caturus, 

 Upper Jurassic of Europe. 



Callopterus, Thiolliere. Lithographie Stone of Bavaria and France. 



Eurycormus, Wagner (Fig. 122). Much resembling Caturus, but vertebral 

 column eonsisting of hemi-vertebrae, which become two similar complete rings 

 in the caudal region. 'Dentition comparatively feeble. E. speciosus, Wagn., 

 from Lithographie Stone, Bavaria. Other species in Oxford and Kimmeridge 

 Clays, England. 



