SELACHIT. 
Eleven more or less fragmentary teeth; Cambridge 
Greensand, Cambridge. Purchased , 1862. 
SJ 
46363. Three teeth, probably of upper jaw; Cambridge Greensand. 
Cunnington Coll. 
v P. 5369. Twenty more or less fragmentary teeth; Cambridge 
Greensand. Presented by James Carter , Esq., 1887. 
IMotidaims serratissimus, Agassiz. 
1776. 
1843. 
Bens Squali, G. Brander, Fossilia Hantoniensia, fig. 111. 
Notidanus serratissimus , L. Agassiz, Poiss. Foss. vol. iii. p. 222, 
pi. xxxvi. figs. 4, 5. 
1883. Notidanus serratissimus, H. B. Geinitz, Abh. naturw. Ges. Isis 
Dresden, p. 108, woodcut. 
1886. Notidanus serratissimus , A. S. Woodward, Geol. Mag. [3] vol.iii. 
p. 216, pi. vi. figs. 23-26. 
• Type, Detached teeth. 
Principal cone of lower lateral teeth relatively large, with nume¬ 
rous strong anterior serrations, diminishing in size downwards ; 
secondary cones sometimes as many as eight in number. 
The specimens in the collection might, at first sight, be regarded 
as pertaining to two distinct species, the small teeth described and 
figured by the present writer, loc. cit. p. 216, pi. vi. figs. 24-26, 
being very different in character from the type-specimens made 
known by Agassiz. A fossil in the Museum of Practical Geology, 
however, shows that the former are immature teeth, evidently 
referable to a lateral position in the lower jaw of this species. The 
teeth first described were thus probably situated in the upper jaw. 
A tooth from the Lower Miocene of Zabrze, Silesia, described by 
F. Boemer \ may belong either to this species or to N. primigenius. 
Some teeth from the Pliocene of Tuscany 1 2 are also very similar to 
the type specimens of N. serratissimus , and these are associated with 
small lower teeth (so-called N. targionii) closely resembling those 
alluded to above. 
Form. Sf Loc . Lower Eocene (London Clay) : London Basin. 
Upper Eocene : Helmstedt, Brunswick. 
24618. Nine teeth of the typical form ; Isle of Sheppey. One is 
figured by the present writer, loc. cit. pi. vi. fig. 23. 
Purchased , 1850. 
1 Geol. von Oberschlesien, 1870, p. 379, pi. xlviii. fig. 1. 
2 N. microdon, R. Lawley, Atti Soc. Tosc. vol. iii. 1877, p. 70, pi. ii. fig. 2. 
