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A EEVISION" OF THE PLIOCENE NON-MARINE MOLLUSCA 

 OF ENGLAND. 



By A. S. Kennaed & B. B. Woodwaed, F.L.S., etc. 



Read Wth November, 1898. 



Although the non-marine moUusca of the pliocene deposits of this 

 country have received considerable attention, the state of our knowledge 

 concerning them is nevertheless not very satisfactory. Much of our 

 information is out of date, whilst the whole of it is so scattered through 

 various journals that it entails a large amount of research to find the 

 different records. Hence it has appeared desirable to collect all the data 

 available, and by checking the various identifications, as far as possible, 

 from the specimens themselves, to establish the record on a more 

 satisfactory basis. The pliocene non-marine moUuscan fauna is of 

 great interest both to the geologist, endeavouring to restore a true 

 picture of pliocene times, and to the malacologist, struggling with 

 problems of distribution, because it is in the K,ed and Norwich Crags 

 that the genesis of our present molluscan fauna is to be sought. It 

 is a noteworthy fact that many of our existing species are met with 

 for the first time in these beds, and are not known to have existed 

 on the continent till a much later date. This may result from the 

 imperfection of the geological record, or it may indicate that these 

 forms have been derived from a region to the northward, and it is 

 worthy of remark, as giving additional weight to this latter hypothesis, 

 that there are forms in North America closely allied to the species 

 under consideration. Some of the operculate aquatic forms also occur 

 in the Congeria Beds, and are therefore presumably members of the 

 old Aralo-Caspian fauna; whilst a few of the species are as yet 

 totally unknown in the fossil state on the continent. 



The finest series of pliocene non-marine mollusca is undoubtedly 

 that comprised in the Searles Y. Wood Collection now at the British 

 Museum (Natural History) ; whilst there is a fair series in the general 

 collection there, in addition to the unique specimens from AValton and 

 Hollesley, formerly belonging to the late Mr Robert Bell, that are 

 now being arranged for public exhibition. The Canham Collection, 

 preserved in the Ipswich Museum, also contains several interesting- 

 examples, whilst Mr. Reeve's specimens are in the Norwich Museum. 



Before proceeding further, we would like to take this opportunity 

 of returning our sincerest thanks to those gentlemen who so kindly 

 permitted us to examine the specimens under their charge, or in 

 their possession, as well as to those who have so freely rendered 

 assistance in other ways in the compilation of this paper. We refer 

 more particularly to I)r. Henry Woodward, Mr. K,. Bullen Newton, 

 and Mr. E. A. Smith, of the British Museum (Natural History) ; 

 Mr. E. T. Newton and Mr. H. A. Allen, of the Museum of Practical 

 Geology ; Mr. James Keeve, of the Norwich Castle Museum ; 

 Mr. Woolnough, of the Ipswich Museum ; Mr. H. W. Burrows, 

 Mr. E. R. Sykes, and Mr. Clement Reid. 



VOL. III. MAKCH, 1899. 13 



