PART II. CHAPTER XIV. 



179 



Eocene Strata Fossil Shells. 



The overlying Eocene deposit consists of two portions ; the 

 upper of blue clay, with occasional cement stones, as before 

 mentioned ; the lower of various coloured sands and clays ; the 

 fossils throughout all the beds being very different from those of 

 the crag. Scarcely any one of the shells can be identified with 

 species now living ; and the whole assemblage is such as to 

 resemble the testaceous fauna of the tropics. This opinion is 

 favoured by the occurrence of many species of Mitra and Voluta, 

 a large Cyprae, a very large Rostellaria, and shells of the genera 



FOSSIL SHELLS OF THE LONDON CLAY. 



Fig. 137. Fig. 138. 



one third of nat. size. 



Fig. 140. Fig. 141. Fig. 142. 



JSTauWus centralis. Valuta athlcta. TercbeUum 



fusiforme. 



