88 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 13, 



be found witli the shiugle on any West of England beacli at the pre- 

 sent day ; a great mass of flint shingle occupies the middle portion 

 of the Channel far beyond the range of the chalk strata on the 

 coast : and these yery raised beds must haye continually supphed a 

 portion ; the difference consists in the amount of wear, and rela- 

 tiye proportion — on the present beaches they are exceedingly scarce, 

 and only m the condition of rounded shingle : the hke holds good 

 with respect to the raised maiine beds with chalk-flints at eyeiy other 

 place. 



Sir H. De la Beche has noticed the presence of chalk-flmts in the 

 *' raised beaches " he has described on the coast of Cornwall, and 

 adds, " The occuiTence of these flints, as at Coyerach Coye and at other 

 places in the Lizard district, while they are not found inland in the 

 adjoining country, is not easy of explanation*." On the other side 

 of the Channel a like mixtm-e of chalk-flints with other materials • is 

 described by Sir W. Treyelyan in the raised maiine beds about the 

 Channel Islands f. Such facts clearly indicate that the marginal 

 moyement of the materials, dmiugthe period of accumulation of these 

 raised deposits, was from east to west along either side of the Channel, 

 or the reyerse of what takes place at present. 



These accumulations haye hitherto been noticed as proofs of re- 

 cent changes; but in my communication on the subject in 1834, I 

 noticed the poyerty of the marine fauna of the period to which they 

 belonged, and suggested that the sea-waters were then less fayourable 

 to marine hfe than at present, owing to a lower temperature. If the 

 obseryations of the seyeral geologists who haye described the pleisto- 

 cene period and its beds J be kept in mind, when considering the 

 raised beds of the West of England and coast of France, it wiU lead 

 I think to the inference that they also belong to the pleistocene epoch. 

 The raised marine beds of the coasts of Cardigan and Merioneth can- 

 not be separated from the pleistocene beds of Wicklow and the op- 

 posite coast. The inten-ention of the area of the Bristol Channel 

 is not sufiicient to cause similar deposits on the north coasts of 

 Somerset, Deyon, and Cornwall, to be considered of a different age 

 from those on the Welsh coast. From the Irish Channel to the 

 western coasts of England, and to those of France and the Channel 

 Islands, we haye a continuous series of hke phsenomena ; and if one 

 portion is of pleistocene age, so is the whole. 



The bearing which this yiew of the age of these deposits has on the 

 physical histoiy of the English Channel is not without interest. A 

 portion of the pleistocene httoral zone of sea-bed is presei-yed on the 

 coast of Sussex, where it was first noticed and most accurately described 

 by Dr. Mantell : these beds serve to connect the history of the east 

 and west extremities of the Channel. The Brighton beds contaiu (as 

 is well known from Dr. Mantell' s description, as also to all those who 

 may haye examnned them) that admixture of foreign crystallhie rocks 

 which is so characteristic of the pleistocene accimiulations of the 



* Report ou Devon and Coru-uall, pp. 429-646. 



t Proceedings of the Geological Society, vol. vii. p. 577. 



J More particularly Mr. ]\Ioms on the valley of the Thames. 



