276 
SELACHII. 
Hybodus sp. inc. (? striatulus, Agassiz). 
Teeth -with a very high, much compressed crown; median cone 
moderately broad; lateral cones one, two, or three in number, the 
inner pair very long, slender, and pointed. Coronal surface marked 
with numerous delicate vertical wrinkles, rarely extending more 
than half the height of the median cone, but often reaching the 
apices of the lateral cones. 
These teeth are most probably referable to the species indicated 
by the dorsal fin-spines named Hybodus striatulus, Agassiz 1 ; but 
there is } r et no' evidence of association, and other spines occur in 
the same beds. A verv similar tooth from the Weal den of Hanover 
is named H. polyprion by C. Struckmann, Wealden-Bild. Umgegend 
Hannover (1880), p. 58, pi. iii. fig. 9. 
Form. Sf Loc. Wealden : Tilgate Forest, Sussex. 
2685, 2693, 2692, 2597, 3027, 3029, 3032, 3136, 3139-41, 3144, 
3147-8. Sixteen teeth, some very fragmentary, one shown 
of the natural size in PI. XT. fig. 15. Mantell Coll. 
26024, 26026, 28038. Three teeth and two fragments, one shown 
of the natural size in Pi. XI. fig. 14. Dixon Coll. 
P. 1276, P. 5823. The abraded principal cones of two similar teeth, 
figured among the type specimens of Meristodon paradoxus 
by L. Agassiz, tom. cit. pi. xxxvi. figs. 53, 54. 
Egerton Enniskillen Colls. 
28410, 23420. Xine more or less perfect teeth. Mantell Coll. 
48377. Median cone of a very large smooth tooth. Purchased, 1877. 
P. 2844. Two teeth and two imperfect associated teeth. 
Enniskillen Coll. 
Three fragments, possibly of similar teeth, have also been obtained 
from the Lower Greensand of Godaiming, Surrey. 
(P. 5520. Caleb Evans Coll.) 
£3ybodus sp. inc. 
Teeth with a relatively low crown ; lateral denticles broad, two 
or three in number; coronal surface marked by few widely spaced 
wrinkles, many extending to the apices. 
Form. 6f Loc. Wealden : Sussex. Xeocomian : Isle of Wight. 
28420 a. Specimen figured of the natural size in PI. XI. fig. 16 ; 
Tilgate Forest. Mantell Coll. 
1 L. Agassiz, tom. cit. p. 44, pi. viii. b. fig. 1. 
