538 proceedings of the geological society. [june 20, 



June 20, 1866. 



The following commnnications Avere read : — 



1. On the Stetjcture of the Red Ceag. By S. Y. Wood, P.G.S. 

 Mr. Prestwich has, I believe, for several years inclined to the 

 opinion that the Eed and Pluviomarine Crags are coeval; but, so 

 far as I am aware, he has not expressed that opinion in print. In 

 1863 my son had arrived at a similar conclusion ; and in a paper 

 by him, published in the ' Ann. & Mag. Nat. Hist.' for March 1864, 

 he showed that the Chillesford beds overlie alike both the Eed and 

 Fluviomarine Crags, and that the Eed Crag itself was not aU of 

 one age, but divisible into distinct portions, the uppermost of which 

 he regarded as newer than the Fluviomarine, and intermediate in 

 age between it and the Chillesford beds. 



In December 1864 another paper by my son was read before this 

 Society (but was afterwards withdrawn, and an epitome of it, 

 together with a map of the Upper Tertiaries of the East of England, 

 printed for private circulation), wherein he contended that the so- 

 called Weybourne Crag, the Cromer Boulder Till, and the Contorted 

 Drift formed a separate series, to which he assig-ned the term 

 *' Lower Drift," and that this in common with the Eed and Eluvio- 

 marine Crags was overlain by the great body of sands which inter- 

 vene between the Crag and the Boulder-clay, and to which he ap- 

 plied the term " Middle Drift," distinguishing the Boulder-Clay as 

 the " Upper Drift." 



In November 1865 a paper, by the Eev. 0. Eisher, was read 

 before this Society (and published in their ' Quarterly Journal,' Eeb. 

 1866), wherein he impugns the position of superiority which had 

 been given to the Chillesford beds, and assigns their position in the 

 following descending order : — 1st, Eluviomarine (Norwich) Crag ; 

 2nd, Chillesford Clay; 3rd, Mya-bed beneath the Clay; 4th, Eed 

 Crag. 



In this state of things I determined with my son to reexamine 

 the whole country between Woodbridge and Easton Bavent Cliff; 

 and the result of that examination appeared to show the undoubted 

 superiority of the Chillesford beds to the Eluviomarine Crag in the 

 case of the pit at Thorpe, near Aldborough, as also in the pits at Bul- 

 champ and Wangford. 



In the first place I examined and collected from the shell-bed at 

 the foot of Easton Cliff, and also in the pit found by Mr. Eisher at 

 Yam Hill. I quite agree with that gentleman that it is exactly 

 the same bed as that in the micaceous sands discovered at Chillesford 

 by Mr. Prestwich and others in 1849, and which Mr. Eisher 

 designates as the Mya-bed, — the only difference being that the 

 Easton and Yarn Hill development of it points to a somewhat 

 estuarine character, by the absence of 3Iya trimcata, so common in 

 it near Chillesford, and by the substitution for that shell of Mya 

 arenaria — a feature which the Yarn-Hill and Easton bed shares 

 with what (as my son informs me) is identically the same bed, 

 recently discovered by Mr. Eose at Toft Monks, on the Waveney, 



