BEACHES, ETC., OF THE SOUTH OP E]!«^GLAND. 



313 



lives on water-plants and frequents marshes, can pass over land- 

 surfaces, while the Limncea truncatula is nearly amphibious, being 

 more frequently met with out of the water than in it ; it is also 

 found in very elevated spots. The relative numbers of the various 

 shells are given below. The bones that occurred in quantities at a 

 few places, and none elsewhere, were mostly broken, but not at all 

 rolled or water-worn. The state of preservation of some of the 

 bones is remarkable ; they have lost so little of their animal matter 

 that the bone hardly adheres at all to the tongue, and looks almost 

 as fresh as a recent bone. Dissolved in dilute hydrochloric acid, 

 they leave a mass of flocculent gelatinous matter as residue. A bone 

 of Bison from near the base of the rubble was found to contain 

 17'35 per cent, of organic matter. E-ecent bones of Ox contain 

 about 30 per cent. 



The organic remains of the Chilton Drift comprise : — 



Elephas primigenius. 

 Bhinoceros tichorhinus. 

 Bison priscus (?). 



'No. of specimens 

 found. 



Pupa marginata 226 



Helix hispida 53 



Limax aqrestis 1 



Equus caballus. 

 Cerms elaphus. 

 Cervus tarandus. 



No. of specimens 

 found. 



Limncea truncatula 3 



Planorbis albus 1 



Succinea ohlonga 11 



My object at that time being only to direct attention to the 

 interest of the section, I did not give the further extension of this 

 deposit. This has since been done by Mr. Jakes-Browne,^ who 

 mentions also several analogous deposits in other areas ; but though 

 analogous, they are wanting in the palaeontological and stratigra- 

 phical evidence of the type-sections at Brighton and Sangatte. He 

 thinks also that rainwash would account for much of the Chilton 

 deposit, but for various reasons I cannot subscribe to this opinion, 

 nor can I think that the contour of the ground has been greatly 

 modified since the accumulation of this deposit. 



A trail of large blocks of sarsenstone is prolonged by the Hag- 

 bourne villages, to a level about 100 feet lower, on to the outcrop of 

 the Upper Greensand. Other slopes along these Downs exhibit 

 similar trails of sarsenstone. 



(10) Wallingford. — It is probable that the spread of unstratified, 

 coarse flint-gravel covering the corresponding Chalk plain which, on 

 the east side of the Thames Valley, extends from Turner's Court 

 above WaUingford to the neighbourhood of Ewelme, may be of the 

 same age. It presents, however, a very different appearance, 

 forming a more persistent bed, composed of somewhat large angular 

 and unrolled chalk-flints embedded in an ochreous sandy clay, but 

 containing a few small irregular patches of chalk-rubble, as though 

 caught up when in a more compact state, and a few seams of 

 sand. The difference of structure is no doubt owing to the circum- 

 stance that the adjacent Chiltern Hills are capped by a Bed Clay- 



Proc. Geol. Assoc, vol. xi. (1889) p. 204. 



y2 



