CHALK. 409 



The Middle Chalk of Swaffham is well known through the labours of C. B. Rose ; 

 it yields Cardiaster {Infitlaster) cxcentricus, etc.^ There are Chalk-pits at Litcham, 

 and at Kenninghall and Bridgeham, near East Harling. BdeniniUlla qiiadrata, 

 Osirea acutirostris, etc., occur in the Upper Chalk near Walsingham, at Guist, near 

 Fakenham, and at Banham.* 



The uppermost beds of Chalk near Norwich are characterized 

 by the presence of the gigantic flints termed paramoudras or pot- 

 stones, often three feet in length and one foot in diameter, which 

 are found at Horstead, Catton, Trowse, Thorpe, etc. (See p. 399.) 

 The Chalk of Norwich contains Belamiitella mucronata, B. lanceolata, 

 Ostrca vesicnlaris, Peden cojicentricus, Chama inceqiiirostrala, Terehra- 

 tula carnea, RhynchoJtella plicaiUis, var. octoplicata, Attanchytes ovatus, 

 Cardiaster granulosus, etc.^ Remains o{ Mosasaurus [Leiodoii anceps) 

 have been obtained by Mr. T. G. Bayfield at Lollard's Pit, near 

 Bishops Bridge, Norwich.* The highest beds of Chalk known in 

 Norfolk are those which occur at Trimingham ; they contain 

 Trochosmilia coniucopicE, Ostrea larva {canaliculata or liinata), which 

 occur in the newest zone (Danian) of European Chalk, and Ostrea 

 vesicnlaris {Gryphcoa globosa), etc.^ Hence the highest Chalk of 

 Norfolk has been sometimes compared with that at Maestricht, 

 in Holland, and Faxoe, in Denmark, in which countries the Chalk 

 exhibits gradations into the Tertiary strata. 



The Upper Chalk is shown in the cliffs between Sherringham 

 and Weybourn, beneath the Glacial Drift, and eastwards it occurs on 

 the foreshore (see p. 398) as far as Cromer. The bluff at Triming- 

 ham, although in situ, has been disturbed and elevated by Glacial 

 agency. (See sequel.) 



The thick beds of flint-gravel, especially those on Household, Poringland, and 

 Strumpshaw Hills, testify to the great destruction of the Chalk ; and they are 

 of considerable interest from the many organic remains that have been found in 

 the flints ; these include many Sponges, etc., and some species not met with in the 

 Chalk of the neighbourhood. Echinoconiis conicus {Galerites albog,aleriis), met with 

 in the gravel, has not been recorded from the Norwich Chalk. Flint casts of 

 Cliona-borings are frequent in shells of Belemnites and luoceramus. S. Wood- 

 ward also mentions the occurrence of spherical flint-pebbles having a nucleus 

 originating in a sponge ; these are sometimes loose, the pebbles are then called 

 Eagle-stones, or /Elites (a name given by Pliny). There is, however, no founda- 

 tion for the notion that the sponges indicate a higher zone of Chalk than is 

 developed at Norwich.^ 



In Suffolk the Chalk is exposed at Claydon, near Ipswich, 

 Needham Market, Sudbury, Bury St. Edmunds, and Brandon. 

 (See sequel.) At Combs, near Stowmarket, a deep well penetrated 



^ Proc. Geol. Assoc, i. 231. 



^ Geol. Fakenham, etc. (Geol. Sm-vey), p. 7 ; and F. J. Bennett, Geol. Attle- 

 borough, etc. p. 4. 



^ Geol. Norwich (Geol. Survey), p. 8 ; Proc. Norwich Geol. Soc. i. 239. 



* G. Mag. 1864, p. 296. 



^ C. Reid, Geology of Cromer (Geol. Survey), p. 5. 



^ Geol. Norwich (Geol. Survey), p. 26 ; see also remarks on flints of Surrey 

 by Godwin-Austen, Proc. Geol. Soc. iv. 168. 



