382 Geological Society : — 



review of the whole question he arrived at the following conclu- 

 sions : — first, that there is only one Old Eed Sandstone properly so 

 called — represented in Devonshire by the Pickwell-Down Sandstone, 

 in Ireland by the so-called Upper Old Eed Sandstone (including the 

 Kiltorcan beds), in Scotland by the so-called Upper Old Eed Sand- 

 stone, and in Belgium by the " Psammites du Condroz ; " secondly, 

 that the so-called Old Eed Sandstone of Herefordshire is the estua- 

 rine representative of the Middle and Lower Devonians of Devon- 

 shire, and that the so-called Lower Old Eed Sandstone of Scotland, 

 with its fish-remains, is the lacustrine representative of the Upper 

 Silurian rocks. In conclusion the author discussed the physical 

 conditions under which these various formations were deposited. 



March 24, 1880.— Eobert Etheridge, Esq., E.E.S., 

 President, in the Chair. 



The following communication was read : — 



1. "The Newer Pliocene Period in England. — Part I. Com- 

 prising the Eed and Pluvio-marine Crag and Glacial formations." 

 By Searles V. Wood, Esq., Jun., F.G.S. 



The author divided this part of his subject into five stages, com- 

 mencing with 



Stage I. The Eed Crag and its partially fluvio-marine equivalent. 

 The Eed Crag he regards as having been a formation of banks and 

 foreshores mostly accumulated between tide-marks, as shown by the 

 character of its bedding. The southern or Walton extremity of 

 this formation, which contains a molluscan fauna more nearly allied 

 to that of the Coralline Crag than does the rest of it, became (as did 

 also the rest of the Eed Crag south of Chillesford and Butley) con- 

 verted into land during the progress of the formation ; while at its 

 northern or Butley extremity the sea encroached, and an estuary 

 extending into East Norfolk was also formed ; during which geo- 

 graphical changes a change took place in the molluscan fauna, so 

 that the latest part of the Eed Crag proper and the earliest part of the 

 fluvio-marine (both containing the northern species of mollusca and 

 those peculiar forms only which occur in older glacial beds) alike 

 pass up without break into the Chillesford sand and laminated clay, 

 which form the uppermost member of the formation. He also 

 regards the principal river of this estuary as flowing into it from 

 North Britain, through the shallow preglacial valley of chalk in 

 which stands the town of Cromer, and in which the earlier beds of 

 Stage II. accumulated in greatest thickness. The forest and fresh- 

 water beds, which in this valley underlie the beds of Stage II., he 

 regards as terrestrial equivalents of the Eed Crag ; and having ob- 

 served rolled chalk interstratified with the base of the Chillesford 

 clay in Easton-Bavent cliff, he considers this to show that so 

 early as the commencement of this clay some tributary of the Crag 

 river was entered by a glacier in the Chalk country, from which 

 river-ice could raft away this material into the estuary. He also 

 regards the copious mica which this clay contains as evidence of ice- 

 degradation in Scotland having contributed to the mud of this 

 river. 



In Stage II, he traced the conversion of some of this laminated 



