BIVALVIA. 177 



This appears to differ from squamosa in having rather more fimbriated lamellae, but it 

 is doubtfully distinct. M. Deshayes has united two shells previously considered by 

 himself as specifically separated. From this I presume the French specimens present 

 great variations. Our specimen appears to be intermediate between the two varieties 

 rusticula and suhstriata. 



8. Chama prisca, S. Wood. PI. XXV, Bg. 10. 



Locality. London Clay. Railway-cutting, Finchley. 



The figure referred to represents a small shell received from Mr. Edwards witli the 

 above locality attached. This is the first specimen that either Mr. Edwards or myself 

 have seen from any Eocene deposit in England below the beds of either Barton or 

 Bracklesham. It is the upper valve, and has been somewhat rubbed. Its imperfect con- 

 dition unfits it for satisfactory specific determination, but I imagine it to be distinct, from 

 its strongly marked radiations and its imperfect or obsolete concentric fimbriae. 



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