A MONOGRAPH 



OP 



THE CRAG MOLLUSCA, 



OK, 



DESCRIPTIONS OF SHELLS 



FKOM THE 



MIDDLE AND UPPER TERTIARIES OF THE EAST OF ENGLAND. 



BY 



SEARLES Y. WOOD, F.G.S. 



CONTINUATION OF 



BIVALVES. 



LONDON: 



PRINTED FOR THE PAL^ONTOGRAPHICAL SOCIETY. 

 1853. 



