216 A. Smith Woodward — On the Genus Notidanus. 



allies in a formation said to be of Cretaceous age in New Zealand is 

 a very remarkable circumstance. 1 



13. N. serratissimus, Agassiz. Plate VI. Figs. 23-26. 



1766. Dens Squall, G. Brander, " Fossilia Hantoniensia," fig. 111. 



1843. iV. serratissimus, L. Agassiz, "Bech. Poiss. Foss." vol. iii. p. 222, pi. 36, 



figs. 4, 5. 

 1870. „ „ F. Bonier, " Geologie von Oberschlesien," p. 379, pi. 48, 



fig. 1. 



This species was founded upon two teeth from the London Clay 

 of Sheppey, said to be preserved in the collection of Dr. Bowerbank, 

 but not now recognizable among the specimens acquired by the 

 British Museum. The teeth are comparatively small — the largest 

 I have examined not attaining a length of two centimetres — and the 

 total number of cones appears to vary from five to ten, according to 

 the situation in the mouth. The principal cone is only slightly longer 

 than the first of those immediately following, but it is somewhat 

 moi'e robust and has its anterior edge much produced forwards and 

 strongly indented with a series of regular serrations throughout half 

 its length. The apices of all- the cones are more or less blunt. 



Fig. 23 represents a typical tooth of this species, such as was 

 known to Agassiz. I have not succeeded in satisfactorily deter- 

 mining whether it appertains to the upper or the lower jaw ; but in 

 addition to this form the London Clay also yields a number of more 

 elongated teeth, which are undoubtedly referable to the mandibular 

 series. An adult specimen is preserved in the Museum of Practical 

 Geology, and there are several immature examples in the British 

 Museum. Three of the latter are shown in Figs. 24-26, and, except 

 in size, they only differ from the adult in being either destitute of 

 anterior serrations or exhibiting very delicate traces of them. 



In England, N. serratissimus appears to be almost exclusively 

 confined to the London Clay, rarely occurring in the Middle Eocenes 

 of Barton and Bracklesham. On the Continent, however, Dr. Komer 

 has described (loc. cit.) a similar tooth from the Lower Miocene of 

 Zabrze, Silesia. 



14. N. primigenius, Agassiz. PL VI. Figs. 19-22. 



1843. N. primigenius, 1j. Agassiz, " Bech. Poiss. Foss." vol. iii. p. 218, pi. 27, 



figs. 4-8, 13-17. 

 1843. N. renurvus, L. Agassiz, ibid. p. 220, pi. 27, figs. 9-12. 

 1849. N . primigenius, B. "W. Gibbes, Journ. Acad. Nat. Sci. Philad. ser. 2, vol. i. 



p. 195, pi. xxv. fig. 95. 

 1852. „ „ A. Quenstedt, " Handb. Petrefakt." p. 167, pi. 13, fig. 3. 



1858. ,, „ J. Probst, Wiirttb. Jahresbefte, vol. xiv. pp. 124-127. 



1877. „ ,, B. Lawley, Atti Soc. Toscana Sci. Nat. pp. 66-68, pi. i. 



figs. 1-5. 

 1877. N. recurvus, B. Lawley, ibid. pp. 69, 70, pi. ii. fig. 1. 



1879. ,, ,, J. Probst, Wiirttb. Jahresb. vol. xxxv. pp. 162, 163, pi. iii. 

 figs. 12-17. 



1 In addition to Notidanus dentatus, tbe National Collection also comprises tbree 

 teeth of Uxyrhina and one of Odontaspis from these beds ; the former bear a very 

 close resemblance to the common 0. Mantelli of the European Cretaceous, though 

 there are not sufficient materials to establish their identity ; and the Odontaspis is 

 indistinguishable from the well-known 0. subulata of the same age. 



