466 



PLIOCENE. 



borealis, Bticcinum undatum, var. tenerum, etc., all of which are found 

 in the lower bed. 



The upper bed at Bramerton has been correlated by INIessrs. 

 Wood and Harmer with the seam of shells at Brundall, and with 

 the Crag at Aldeby, Horstead, and Burgh near Aylshani. 



Bramerton has always been the chief collecting ground in the Norwich Crag. 

 Sowerby's specimens were nearly all obtained from this locality ; so also were 

 those enumerated by Mr. S. V. Wood in his "Crag MolUisca." Tcllina Balthica 

 therein recorded by him has been subsequently regarded as erroneous : it has 

 never been met with by Mr. James Reeve during his exhaustive examination of 

 the beds. To Mr. Reeve indeed we are mainly indebted for our present know- 

 ledge of the Bramerton Crag fauna. ^ 



An excellent section of the Norwich Crag Series is exposed at 

 Thorpe, near Norwich, and here, although some divisions can be 

 indicated, there is no conspicuous bed of Chillesford Clay, and no 

 distinction between Fluvio-marine Crag and ' Chillesford shell-bed.' 



Fig. 79.— Crag-pit at Thorpe, near Norwich. 

 (Prof J. Prestwich.) 



4. Oclireous flint-shingle 

 and sand, with a 

 layer of iron-sand- 

 stone at. v containing 

 casts of Mollusca. 

 Deer's horn. 2ofeet. 



't\-y^.'^' 



3. Grey clay, i to I5 feet. 



2. White and buff sands 

 with seams of gravel 

 and patches of shells 

 largely comminuted. 

 5 to 12 feet. 



1. Stone-bed made up of 

 unrolled and little- 

 worn flints, with 

 Mammalian re- 

 mains, etc. I foot. 



a. Chalk with flints. 



The top bed (4) has yielded Nucida CobhoIdicB, Tellina ohliqiia, etc.^ 

 The beds are numbered according to the series of strata noted 

 previously (p. 463). 



The Fluvio-marine Crag beds are shown also at Whitlingham, 

 Arminghall, and at Postwick near Norwich, at Bulchamp, Wang- 

 ford (10 feet), Yarn Hill, near Potters Bridge, Southwold, Dunwich, 

 and Thorpe near Aldborough in Suffolk ; they have also been 

 exposed at Ditchingham near Bungay. At Whitlingham three 

 distinct layers of shells have at times been exposed, and there it is 

 impossible to distinguish the local divisions that are indicated in 

 the section at Bramerton. (See Fig. 80.) 



Chillesford Beds.— The Chillesford Beds were so named from 

 Chillesford near Orford, in Suffolk, where the beds were described 



' Proc. Norwich Geol. Soc. i. 69, no. 



- Geol. Norwich, p. 75 ; Prestwich, G. Mag. 1870, p. 539, Q. J. xxvii. 469. 



