MARINE DEPOSITS. .555 



Upwards of 70 species of Mollusca, all Recent forms, have been obtained from 

 this Mud-deposit, and they have a somewhat more southern aspect than those of 

 the present English Channel. They include Pholas crispata, Saxicava, Scrobicu- 

 laria plana, Caniium cdnle, Nucula nucleus, Fiillastra aitrea. Tapes decussata, 

 Pecten maxiiniis, P. opercularis, P. polymorphus, Ostrea edttlis, Trochus cincraritts, 

 etc. The Mammalia include Elephas priinigenms, E. antiquiis, etc. 



Mr. T, Codrington has described the remains of an old sea-bed at Avisford 

 and Waterbeach, near Goodwood, with marine shells, at from 80 to lOO feet 

 above the sea-level.' Near Brighton the old sea-beach (see p. 495) is from 8 to 

 12 feet above the present beach, and has been traced by Prof Prestwich past 

 Arundel to Chichester and Bourne Common, where it is from 100 to 140 feet in 

 height.- 



At Roxholme, near Sleaford, and at Holbeach, sandy beds with marine shells 

 have been observed. •^ Marine gravels and sands occur also near Tattersall, Bourn, 

 Whittlesey, March, and other places, and they are known as "Fen Gravels." 

 Corbiculaflitminalis, also remains of Rhinoceros, Mammoth, etc., have been found 

 at some localities.* (See pp. 499, 530.) 



Brickearth of the A-^a?'.— This deposit, so well known through the labours of 

 Mr. C. B. Rose, occurs in West Norfolk, in the valley of the Nar (a tributary of 

 the Great Ouse).^ The brickearth, a bluish sandy clay, has been traced from 

 Narford to West Bilney and Watlington. It has a thickness of 20 feet or more, 

 and contains, amongst other shells, Turrilella terebra, AporrJiais pes-pelicani, 

 Liitorina littorea, Natica nitida, Ostrea edulis, Tcllina Balthica, Scrobicidaria 

 platta, etc. Bones of Rhinoceros, Mammoth, etc., also occur. The shells are in 

 fine preservation ; and there can be little doubt that the deposit was formed in an 

 estuary. 



At Hunstanton, near the gas-works, there are ballast-pits showing sand and 

 gravel (Hunstanton gravel), with recent species of marine shells, Ostrea, Cardtutn, 

 Mytiliis, Nassa, Biiccinum, etc. Near the pier there is a similar accumulation 

 about 10 feet above high-water mark, which has been described as a Raised 

 Beach." 



Deposits of marine sand and shingle containing sea-shells occur 

 in some places inland at about the present sea-level, and sometimes 

 beneath it, and indicate the extension of the sea over the area, 

 in comparatively recent times. 



Bnrtle Beds. — Recent marine deposits have been found in the Somersetshire 

 moorlands, and being at one time well exhibited at Burtle, near Glastonbury, 

 they were termed by De la Beche the Burtle Beds. At several places in the 

 moorland the ground rises into gentle hills, generally banks of New Red Marl, 

 with fringing and outlying beaches composed of sand with recent marine shells. 

 The species include Tiochus zizyphiniis. Patella viilgata, Littorina littorea, 

 Hydrobia (Rissoa) tilvce, J\assa reticulata, Pholas Candida, Cardiiun edule, Tellina 

 Balthica, etc' These old lines of beach may be traced along many parts of the 

 border of King's Sedgemoor, at Sutton Mallet, Chedzoy, Weston Zoyland, and 

 Middle Zoy, of which places the three latter retain, in the etymology of their 



^ Q. J. xxvi. 547. See also Meyer, Q. J. xxvii. 82 (Portsmouth). 

 - Q. J. XV. 215. 



2 Rev. E. Trollope, Proc. Geol. Polyt. Soc. W. Riding, p. 637 ; Jukes-Browne, 

 Geol. S. W. Lincohishire, pp. 102, 104. 



* Skertchly, Geol. Fenland, p. 1S3. 



5 Phil. Mag. (2), vii. 196; G. Mag. 1865, p. 8. 



* Seeley, Q. J. xxii. 470 ; Wood and Harmer, Supp. to Crag Mollusca, 

 p. 28; Jukes-Browne, Q. J. xxxv. 415; B. B. Woodward, P. Geol. Assoc. 

 viii. 100. 



' Geol. E. Somerset (GeoL Surv.), p. 103 ; E. T. Newton, Cat. Tertiary and 

 Post-Tertiary Fossils, Mus. Pract. Geol. p. 84. 



