84 PEOCEEDINGS OF THE GEOLOGICAL SOCIETY. 



escarpment C. The beds below c are stratified clays, sometimes 

 mottled, and are said to repose on the lower gravel. This lower 

 gravel is said to be 3 ft. thick ; and at 45 ft. from the surface the 

 chalk is said to be found near D ; but I have not seen this myself. 



Some years since, an excavation was made near M, and chalk 

 was found about 43 ft. from the surface. The false-bedded sands 

 were 20 ft. thick at that point, and covered the upper-gravel series, 

 e, very full of flints and pebbles*. 



The Mammalian remains occurring in the gravel, f, are more 

 rolled than those found in the brick-earth above. 



A list of Grays species has been published by Prof. Morris, and 

 also in the Geological Society's Journal, vol. xxii. p. 101, by Mr. Boyd 

 Dawkins. 



Eeturning to PI, lY. fig. 6, the false-bedded sands are represented 

 thinning out towards the river, as well as the Cyrena-beds. The 

 depth of the chalk below the surface is ascertained by a well-section 

 at F ; and the covering gravel, e, comes in contact with the lower 

 gravel, /, near the railway-cutting, g. Close to this point there was 

 a section of coarse gravel, 12 ft. thick, open in a gravel-pit, reposing 

 upon chalk without any beds of sand or brick-earth. The chalk is 

 said to have been seen in the railway- cutting 9 ft. above the rails 

 at the bridge I. In the tramway east of, and close to. Grays 

 Station, the chalk is also well exposed 6 feet above the rails, with 

 thick beds of gravel lying irregularly upon it, and some brick-earth 

 beds and gravel above them containing comminuted shells derived 

 from the Woolwich series, which beds have been entirely removed 

 by denudation at Grays. In excavating for a cellar near Grays 

 church, a very large mass of sandstone was found about 20 ft. above 

 the Ordnance datum-hne, many tons in weight, in the gravel close 

 to the chalk. Such stones are abundant in the upper gravel in the 

 Chalk and Thanet Sand west of the Grays Station. 



Great changes have taken place at Grays, by removal of brick-earth, 

 since Professor Morris first desciibed the fossils from the Thames- 

 valley deposits ; and he is almost the only geologist who has watched 

 the excavation from year to year. It will be seen from PI. IV. fig. 6, 

 that, like the gravels of the Somme, the fossiliferous brick- earths of 

 Grays are deposited in a concavity of the chalk. The chalk is 15 ft. 

 lower at D than at G, and 43 ft. lower at D than B. The old Thames 

 river seems to have divided into two channels at Grays ; and the 

 fluviatile deposits between C and G appear to have occupied one 

 channel, thus forming the whole series of stratified beds which are 

 intercalated between the gravels e and /. 



The last deposit was the covering gravel- bed, e, which is con- 

 tinuous from the marsh to the point A, and beyond it. 



The position of the section (PI. lY. fig. 7, Erith) A B ST is laid 

 down on the sketch map, Plate IX. ; and A B, the part near the 

 escarpment of the Chalk and Thanet Sands, is enlarged in fig. 17. 

 page 85. Although Erith and Grays are not exactly opposite each 

 other on the Thames valley, yet the sections, Plate lY. figs. 6 and 7, 

 ■^^ I obtained this information from Professor J. Morris, F.Gr.S. 



