206 



FOSSIL FISHES OF THE ENGLISH CHALK. 



face. One dental crown is wrongly ascribed by Agassiz, lor. rif., to Oxyrhina 

 mantelll. A small group of associated teeth from Lewes in the Willett Collection, 

 Brighton Mnsenm, does not exhibit any remarkable variations. 



Iforuoiis ami Localities.- — Turonian zones : LeAves, Honghton, and Anindel, 

 Sussex. 



Genus LAMNA, Cuvier. 



Lamna, G. Cuvier, Regne Animal, vol. ii, 1817, p. 126. 

 Otodus, L. Agassiz, Poiss. Foss., vol. iii, 1843, p. 266 (in part). 



Generic Characters. — Posterior dorsal fin and anal fin very small. A pit at the 

 root of the caudal fin, which has the lower lobe much developed; side of the tail 

 with a keel. Teeth (except the hindmost of the series) with a high and narrow 



H^^^ 



Fig. 62. Lamna cornuhica (Linnceus) ; upper and lower dentition, about one-half nat. size. — Existing. 



compressed crown, not serrated, but flanked with one or two denticles; root bifid. 

 On each side of the upper jaw, at a short distance from the symphysis, one or two 

 teeth comparatively small. 



Type S2^ecies. — An existing shark, Lamna cornuhica. 



Remarls. — The dentition of the type species is shown in the accompanying 

 Text-fig. 62. It can scarcely be distinguished from that of a closely related genus 

 Odoutaspis, but differs in the less elevated and less subulate character of its anterior 

 teeth, and in the usually larger size of the lateral denticles. 



1. Lamna appendiculata, Agassiz. Plate XLIV, figs. 3 — 7; Text-figures 63, 64. 



1822. Sqnahis mnnteJus ?, G-. A. Mantell, Foss. South Downs, pi. xxxii, figs. 2, 3, 5, 6, 9. 



1835. Lamna ap'pendicuJata, L. Agassiz, Poiss. Foss., Feuill, p. 54. 



1843. Otodus appendiculatus, L. Agassiz, Poiss. Foss., vol. iii, p. 270, pi. xxxii, figs. 1 — 25. 



1850. Otodus appendiculatus, F. Dixon, Geol. Sussex, pi. xxx, fig. 25, pi. xxxi, fig. 17. 



1889. Lamna appendiculata, A. S. Woodward, Catal. Foss. Fishes B. M., pt. i, p. 393. 



1894. Lamna appendicidata, A. S. Woodward, Proc. Geol. Assoc, vol xiii, p. 197, pi. v, fig. 25, 



pi. vi, fig. 2. 

 1902. Lamna appendiculata, M. Leriche, Ann. Soc. Geol. Nord, vol. xxxi, p. Ill, pi. iii, figs. 28 — 38. 



