W. H» Dalton — Subsidence in East Essex. 491 



We have therefore as equivalents : 



f Middle Jurassic 



I (Kachh — Jabalpur Group). 



1. Fpper portion of Gondwana Series = Jurassic <^ 



Liassic 

 1 (Rajmahal Series). 

 ■ f Keuper (Upper Trias) 

 ■ I (Panchet Group). 



2. Lower portion of the Gondwanas = Triassic -{ 



I Lower Trias 



(_ (Damudas and Talchirs), 



Two short papers of mine upon this subject have been published 

 in the Eecords Geol. Surv. Ind. vol. ix. Nos. 2, 3 ; a third not yet 

 issued will contain the Flora of the Jabalpur Group, and some sup- 

 plementary notes to my preceding papers. 



My second paper is followed by one, written by Mr. W.T. Blanford, 

 under a special title, but on the same subject. In this the author 

 intends to revive once again the former views, which I trust are now 

 no more tenable, as I have shown suflSciently in this present «hort 

 paper. 



Having himself seen my paper through the press, Mr. W. T. 

 Blanford had of course the earliest opportunity of stating his views 

 on the subject in the same volume ©f the Eecords, before my paper 

 was published. 



In my present short paper I cannot enter into discussion of Mr. 

 Blanford's views, and what I have to say against them will be stated 

 in detail in the next number of our Eecords. 



I hope further examinations of the fossils, as the only guides 

 in determining the age of a Series, will contribute much towards 

 clearing up their relations, concerning which, however, I am already 

 satisfied. 



11. — ^Subsidence in East Essex.^ 



By W. H. Dalton, F.G.S., of H.M. Geological Survey. 

 (Communicated with the Director's approval.) 



THAT the latest movement of the south-east of England has been 

 one of depression is evidenced by the numerous ^' submerged 

 forests" which occur at intervals round the coast, ranging down- 

 wards, not only to half-tide level, but to beyond the lowest ebb ; and 

 therefore not explicable merely on the hypothesis of sheltering sand- 

 bars, or lines of dunes, even where such can be shown to have 

 existed. 



In East Essex, the question is complicated by the variety of possi- 

 bilities that have to be taken into consideration. The rapid waste of 

 the cliffs at Harwich, Walton Naze, and Clacton sufficiently accounts 

 for the disappearance of towns and villages mentioned in ancient 

 records as existing on that part of the coast, as they were almost in- 

 variably erected on land above the sea-level, and therefore liable to 

 be attacked and destroyed by the sea. 



Southward and westward from Clacton, deposition is still going 

 1 Read before the Colchester Natural History Society ,^Oct. 5, 1876. 



