88 



PEOr. J. PEESTWICH 0^~ THE COEEELATIOX OF THE 



10. FuriJier Obseevatio>"s on the Coerelaiion of tJie Eocexe Strata 

 in ExGLAXD, Belgitjm, and the IS^oeth of Praxce. By Prof. 

 Joseph Peest^ich, M.A., F.E.S., F.G.S., &c. (Eead December 

 21, 1887.) 



[Plate V.] 



It is not my intention to reopen the whole qnestion of the position 

 and correlation of the Eocene strata of England and Erance, but 

 merely to bring again before the Society such portions of them 

 as involve some yet unsettled points of classification and some 

 necessary rectifications of my own work. 



The s^^nchronism of the Thanet Sands with the Lower Landenian, 

 of the London Clay with the Lower Tpresian, of the Bracklesham 

 Beds with the Calcaire Grossier, and of the Barton Beds with the 

 Gres de Beauchamp is now perfectly well established. But with 

 respect to the exact relation of the Sands of Bracheux and of the 

 Soissonnais to the English Series, of the Oldhaven Beds to the 

 Woolwich Series, and of the Lower and Upper Bagshots to equiva- 

 lent strata in the Paris Basin, there are still difi'erences of opinion 

 and some open questions. 



Since the publication of my early papers on the Eocene strata, 

 the important monographs on the Eocene Mollusca of Edwards * 

 and Searles "Wood t in this country, and the last great work of 

 Deshayes J in Erance, have made large additions to the Eocene faunas 

 of the English and Erench Tertiaries. At the same time, the work of 

 the Geological Survey and others in the London and Hampshire 

 Basins § ; of WSL. Hebert \], Dolfuss ||, De Mercey ||, and others in 

 the Paris Basin ; of MM. Gosselet ^, Ortlieb, and Chelloneix ** in the 

 IS'orth of Erance ; and of MM. Briart and Cornet, M. Dewalque, 

 MM. Rutot, Yan der Broeck, and others m the Belgian Basin tt, 

 have done much to settle many doubtful points of stratigraphy and 

 palaeontology in the Eocene Series. Especially did the second com- 

 prehensive work of M. Deshayes serve to correct the synonomy of 

 species, and their right location. 



The classification of the Eocene Series, now that the fluvio- 

 marine strata of the Isle of Wight, and a portion of those of the 

 Paris Basin have been relegated to the Oligocene, is generally IX 

 tabulated as follows : — ■ 



* ' The Eocene Cephalopoda and Uniralves.' Pal. See. Monogr. 

 t ' The Eocene BiTalyes.' Pal. Soc. Monogr. 



I 'Histoire des Auimaux sans Tertebres decouverts dans le Bassin de Paris,' 

 2nd series. 



§ 'On the Geology of the Isle of Wight/ by H. W. Bristowe, 1862; 'On 

 the Geology of the London Basin,' by W. Whitaker ; and sundiy papers by 

 Professor Eupert Jones, the Rev. A. Irving, and Mr. Starkie Gardner. 



II Various papers in the BuU. Soc. Geol, de France. 



% Papers in Bull. Soc. Geol. de France, and Ann. Soc. Geol. du IS'ord. 



** ' Etudes geologiques des Collines Tertiaires du Dept. du Nord,' 1871 ; and 

 other papers. 



tt Various papers in Mem. Acad. Eoy. Bruxelles, and Ann. Soc. Geol. du Nord. 



J j Lyell's ' Student's Elements,' 4th edit. pp. 103 and 236 ; Archibald Geikie's 

 •Text-Book of Geology,' pp. 844, 850; De Lapparent's 'Traitede Geologie 

 2nd edit. p. 1163. 



