PLATE L. 



Fig. Page. 



1-3. Ptycliodus latissimus, Agassiz ; three associated teeth of one of the 

 type specimens, in crown- view and outline-section (la-da), nat. size. 

 Figs. 1, 1 a, represent a lower middle tooth. — Turonian zone ; near 

 Lewes. Mantell Collection (B. M. no. 4355). 236. 



4. Ditto ; lower middle tooth, in crown- view and outline-section of crown 



(4a), nat. size.— Chalk ; Hertford. B. M. no. P. 5864. 237. 



5. Ditto; lower middle tooth, in crown-view and outline-section of crown 



(5a), nat. size.— Chalk ; Suffolk. Wetherell Collection (B. M. no. 



37350). 237. 



6-8. Ditto ; associated lower middle tooth, crown-view (6), upper inner 



paired tooth, crown-view (7) and side view (7 a), and lateral tooth, 



crown-view (8) and outline-section (8 a), nat. size. — Turonian zone; 



Burham, Kent, Harford Collection (B. M. no. P. 5603). 237. 



9, 10. Ditto ; associated upper middle tooth (9) and lateral tooth (10), 



crown-views, nat. size. — Turonian zone ; near Lewes. Mantell 



Collection (B. M. no. 4358). 238. 



11. Ditto ; tooth of upper inner paired row, crown-view, nat. size. — Chalk; 



Orford, Suffolk. B. M. no. 36103. 238. 



12. Ditto; tooth of upper inner paired row, crown-view, nat. size. — Chalk; 



near Croydon, Surrey. Bowerbank Collection (B. M. no. 301 20). 238. 

 13-16. Ditto; associated upper teeth of the form named P. dixoni, Dibley, 

 crown-views and outline-sections (13 a— 16 a), nat, size.- — Zone of 

 Terebratulina gracilis ; Cuxton, Kent. Dibley Collection (B. M. 

 no. P. 10260). 238. 



