DESCRIPTION OF PLATE II. 



FOSSIL SHELLS AND TEETH OF MAMMALIA, FROM THE FRESH-WATI .1. 

 EOCENE DEPOSITS. 



SHELLS. 



Fig. 1 Potomomya gregaria j from Headon Hill. 



This shell 13 described by Mr. Sowerbv in Mineral Conehology 

 as Mya gregaria. The genus Potomomya, (river mussels), 

 comprises those species which inhabit rivers only, and are not 

 found in estuaries and brackish waters. 



2. — Potamides concams; Headon Hill. 



3. — Melanopsis fusiformis ; Headon Hill. 



4>. brevis ; Headon Hill. 



5. — Neritina concava ; Colwell Bay. 



0. — Melanopsis carinata ; Colwell Bay. 



7. — Helix (jlobosus ; Shalfleet. 



8 Potamides plicatus ; Headon Hill. 



9. ■ — rentricosus ; Headon Hill. 



MAMMALIAN REMAINS. 



10. — Upper canine tooth of Anoplotherium commune ; from Seafield 



near Ryde. 

 11. — The grinding surface of an upper molar, of Palaotherwm medium ; 



from Binstead. 

 12. — One side of the lower jaw of Palaotherium minus, with five 



teeth ; from Seafield.* 

 13", — A tooth of Diehobnne cervinum, from Binstead. 

 13. — The grinding surface of fig. 13 a . 



With the exception of the gigantic snail-shell, fig. 7, the fossil shells 

 here delineated are abundant at Headon Hill, and in the clays and mails 

 at Colwell Bay. The Mammalian remains are of excessive rarity, and 

 have hitherto only been found in the quarries near Ryde, and at Headon 

 Hill. 



* See British Fossil Mammals, p. 323. 



