816 



TABLE OF DISTRIBUTION. 



mean all the Pliocene and Pleistocene strata^ i. e. all the 

 beds from the Coralline Crag inclusive up to the Alluvial 

 and Peat deposits. This division is convenient^ as the 

 tertiary strata of the Isle of Wight end with upper Eocene, 

 or possibly lowermost Miocene^ whilst in the London 

 district there are no traces of Miocene, and even the 

 upper Eocene is wanting; the gap, therefore, between 

 what may be called the Lower Tertiaries and the Upper 

 Tertiaries in this country is very considerable and well 

 marked.^' 



Table showing the species of Land and Freshwater Mol- 

 lusca which have been described in the foregoing part 

 of this volume — their foreign range — and the occur- 

 rence of any of them as Upper Tertiary fossils. This 

 mark ( — ) signifies their occurrence in the district 

 indicated bv the column. 



Species. 



Aquatic. 



Bivalves. 



Sphasrium corneum 



rivicola 



ovale 



lacustre 



Pisidium amnicum 



fontinale 



pusilliun 



nitidum 



roseuni 



Unio tumidus 



pictorum 



margaritifer 



Anodonta cygnea 



anatina 



Dreissena polymorpha 



15 



o 



14 



c 

 o 



CO 







Distribution in other parts of 

 the worl(L 



14 I 9 



Siberia (Gerstfeldt). 



Siberia. Only one specimen 

 found, and that was in the 

 nasal cavity of a fossil skull 

 of a Rhinoceros. 



Siberia and Kamtschatka. 



Siberia. 



Siberia and Lake Baikal. 



Siberia and Lake Baikal. 



Siberia. 



' ) 



