28 ELOPIFORM FISHES 



which tend to be ovoid and to lack radii. Together these small scales form a basal 

 sheath to the dorsal and anal fins. Enlarged axillary scales are present above the 

 paired fins. 



Appendix to the genus Elops 



Woodward (1901) described a fossil form which he referred to the genus Elops 

 without any distinct species recognition. The Elops sp. is represented by two 

 specimens (B.M.N.H. 39443 and P. 1762) from the London Clay (Ypresian) of Shep- 

 pey, Kent, England. Unfortunately the specimens are poorly preserved and have 

 suffered from pyritization so that very little may usefully be added to Woodward's 

 (1901) description. Elops sp. is certainly larger than any extant species and shows 

 a depression upon the skull roof. This latter feature, although obvious, is of little 

 use taxonomically since the largest individuals of the extant species also show a 

 depression of limited size. The scales of the Eocene Elops are marked in their 

 exposed portion by ridges, but again this is sometimes seen in the Recent species. 

 All features that may be seen of the cranial anatomy, vertebral column and squama- 

 tion suggest that this species is correctly referred to the genus Elops but lack of 

 material results in the Eocene form being left as Elops sp. 



Genus DAVICHTHYS nov. 



Diagnosis. Elopid fishes reaching 120 mm S.L. Head shallow, the length of 

 the cranium forming about 30 per cent S.L. Cranial bones generally smooth. 

 The first infraorbital is rounded and fails to contact the supraorbital. Infraorbital 

 canal with a few moderately long branches ; the union of the antorbital and infra- 

 orbital canals not enclosed by bone. Maxilla extending to the hind margin of the 

 orbit ; two supramaxillae, the posterior marked by a pronounced strengthening 

 ridge. Quadrate with the anterior margin considerably longer than the posterior 

 margin ; quadrate/mandibular articulation well behind the eye. Ceratohyal solid. 

 Preoperculum narrow throughout, the contained sensory canal opening directly 

 to the surface by a few large pores. Vertebral column with 50-56 vertebrae of 

 which 20 are caudal. Pectoral and pelvic fins each composed of 12 rays. Scales 

 small, circular and those in the anterior region of the body marked by four or five 

 weakly defined anterior radii. 



Remarks. The genus is founded on the best known species, Davichthys dubius 

 (Davis) which had been questionably placed in synonymy with Osmeroides gracilis 

 Davis, to which it shows little similarity. 0. gracilis is made the type-species of a 

 new albulid genus Lebonichthys on p. 171. Davichthys is known from the Lower 

 Cenomanian of Morocco and from the Middle Cenomanian and the Upper Santonian 

 of Lebanon. 



Type species. Osmeroides dubius Davis. 



