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PROF. J. PEESTWICH ON THE RELATION OF THE 



risk incurred by the adoption of such meagre divisions ; but in the 

 absence of more important masses of strata, we have unavoidably to 

 depend on these smaller beds, although it must be with the qualifi- 

 cations he names. 



Mr. Woodward states that his conclusions differ from mine in 

 some important particulars, chiefly in the correlation of the beds in 

 several localities. He bases much on the fact that in the general 

 sections I have coloured the Dunwich Cliffs as Glacial Sands *. 

 That, however, in no way affects the special question. Whether 

 the Dtinwich Cliffs, which are much obscured, belong to one division 

 or the other is unimportant. Mr. Woodward satisfied himself that 

 they belong to the Westleton Beds, but Mr. Whitaker has since 

 shown reason to believe that the lower part at all events belongs to 

 the unfossiiiferous sands of the Crag. At one spot they are capped 

 by a small patch of Westleton pebbles with an overlier of Boulder- 

 clay ; while the lower part of the cliff, consisting of sands without 

 fossils, may very probably, as Mr. Whitaker supposes, belong to the 

 Crag t. 



Mr. Woodward objects to Messrs. Wood and Harmer grouping the 

 Bure- Valley Beds as Lower Glacial, and sees no satisfactory palse- 

 ontological reason for separating them from the Norwich Crag, with 

 which he unites them under the name of the " Norwich-Crag Series." 

 He states that " the grounds on which Messrs. Wood and Harmer 

 separated the Bure- Valley Crag from the Norwich Crag have proved 

 to be unsound. The Bure-Valley Crag is palaeontologically identical 

 with the Weybonrn Crag, as they originally pointed out. Both 

 beds contain the Tellina haltliica. But as my colleague Mr. C. Eeid 

 has shown, the Weybourn zone is to be traced at the hase of the 

 Eorest-Bed Series, at Sherringham and other places ; whereas 

 another bed, at a higher horizon, since called the ' Leda-myalis 

 bed ' by Mr. Reid, was also correlated by Messrs. Wood and Harmer 

 with the Bure-Valley Beds. Thus we have a fossiliferous zone at 

 the top and another at the base of the 'Forest-Bed Series,' both of 

 which have been called the Bure-Valley Beds ; and this is the reason 

 why some observers have stated that the Norwich Crag overlies the 

 Forest Bed of Cromer, while others have maintained that the Crag 

 underlies it. The true fossiliferous Bure-Valley Zone, however, as 

 just stated, occurs at the base of the Porest-Bed Series, and is 

 represented by the Weybourn Crag. The Tellina haltliica thus 

 occurs beneath beds which Messrs. Wood and Harmer have grouped 

 as ' Pre-glacial,' and their argument that this shell is confined to 

 Glacial and more recent deposits loses all weight." " For the same 



* I find that I overlooked one of my early note-books, in whicli T bad noted 

 Eoulder-clay and Westleton Sliingle at one point on the top of the clitf', as 

 described by Mr. Whitaker in his ' Geology of ihe Suffolk Coast,' pp. 52-51). 



t In 1871 Messrs. E. T. Dowson and W. M. Crowfoot, of Beccles, found a 

 fossiliferous bed quite at the base of this cliff', from whit-h they procured 44 

 species of shells with a few Man)malian remains. They refer this bed to the 

 Fluvio- marine Crag. 



