FOSSIL AND RECENT 95 



half of the functional oral margin. Supratemporal small and triangular, lying behind 

 the pterotic. Caudal fin with no gap between the second and third hypurals. 

 Body covered by moderately large scales. Scales at the bases of the fins unmodified. 



Type-species. Sal-mo lewesiensis Mantell. 



Remarks. Arambourg (1954) maintained that the correct generic name for this 

 form should be Holcolepis. In this he has been followed by Wenz (1965). Aram- 

 bourg stated that Osmeroides should be used for the myctophiform fish Sardinioides 

 Marck. Goody (1969b) rightly states that the first usage of Osmeroides in a binomen 

 was for Osmeroides lewesiensis (Agassiz 1837 : 5, pis. 60b, c) and this precedes the 

 first usage of both Holcolepis (Marck 1868 : 278) and Sardinioides (Marck 1858). 



Osmeroides lewesiensis (Mantell) 

 (Text-figs. 46-53) 



1822 Salmo lewesiensis Mantell : 235, pi. 33, fig. 12, pi. 34, fig. 3, pi. 40, fig. 1. 



1837 Osmeroides lewesiensis (Mantell) Agassiz : 5 ; pt 1, p. 14, pt 2, p. 105, pi. 60b figs. 1, 2, 

 5, 6, 7 (not figs. 3, 4), pi. 60c. 



1838 Osmeroides mantelli Mantell : 307, fig. 1. 



1878 Osmeroides lewesiensis (Mantell) 



1885 Osmeroides lewesiensis (Mantell) 



1888 Osmeroides lewesiensis (Mantell) 



1895 Osmeroides lewesiensis (Mantell) 



1 90 1 Osmeroides lewesiensis (Mantell) 



1964 Osmeroides lewesiensis (Mantell) 



Fritsch : 32, pi. 7, figs. 5, 6, pi. 8, fig. 1. 

 Laube : 292, pi. 2, figs. 2, 3 and woodcut. 

 Woodward : 322. 

 Woodward : 656, pi. 42. 

 Woodward : n, fig. 2. 

 Danil'chenko : 398, fig. 104. 



Diagnosis (emended). Osmeroides attaining 500 mm S.L. Length of cranium 

 equal to twice the maximum width. Parietals longer than broad. Dermal 

 skull bones showing prominent ornamentation in the form of coarse radiating 

 rugae. Large supraorbital firmly united with the frontal. Parasphenoid extending 

 to the rear of the neurocranium. Complete, ossified interorbital septum. Mandi- 

 bular articulation at mid-orbital level. Branchiostegal rays 18-21 in number, 

 the upper members of the series showing coarse ornamentation. Dorsal fin with 

 18-20 rays, arising midway between snout and caudal peduncle. Vertebrae as 

 long as deep, marked by irregular longitudinal ridges. Caudal skeleton with four 

 uroneurals and three epurals. Scales large, the posterior field with faint tubercles 

 arranged in radiating rows, anterior field showing about five prominent radii. 

 15-17 scales in the transverse series immediately anterior to the dorsal fin. 



Holotype. B.M.N.H. 4294, a specimen showing the head and abdominal region 

 from the Upper Cenomanian (Holaster subglobosus zone) of Lewes, Sussex, England. 



Material. Twenty-five specimens in the B.M.N.H. were examined. B.M.N.H. 

 P. 6456 was prepared in acetic acid and B.M.N.H. 49894 was prepared mechanically. 

 Specimens come from Upper Albian-Coniacian of S.E. England. The Upper 

 Albian record is based on a very imperfect specimen (B.M.N.H. P. 8949) from the 

 Gault Clay at Folkestone, Kent. The opercular bones of this specimen are less 

 ornamented than the Chalk specimens but otherwise there is close agreement. 



