﻿Vol. 64.] SUBDIYISION'S OF THE CHALK OF TRIMINGHAM. 411 



blocks are most bulky at low water and least bulky at high water, 

 the bulk of this large continuous mass must have lain to seawards 

 rather than to landwards of the present coast-line. Moreover, it is 

 quite possible that we have here preserved the last remnants of a 

 land-area that was once in connexion with continental Europe. 



Appendix. 



The Pliocene beds which, as above stated (p. 405), were found 

 directly overlying the Cretaceous, consisted of a coarse dark sand 

 about 9 inches thick, lying on and filling up the inequalities in the 

 surface of a horizontal and practically continuous bed of flint, and 

 succeeded by a bed of dark clay about a foot thick, which was in its 

 turn succeeded by Glacial Clay with horizontal simulated bedding. 

 The sand contained a great abundance of somewhat corroded shells, 

 mainly in drifted masses, and the clay a quantity of Tellince with 

 a few other shells, all in excellent preservation. The sand also 

 contained in great quantity rolled lumps of a grey clay. 



The Glacial Clay must have reached its present position very 

 gently, for a channel in it disclosed a large and delicate, but quite 

 uninjured shell, which rested upon and had its edges embedded in 

 the Pliocene clay, while the greater part of it projected into the 

 Glacial Clay. 



Mr. Clement Eeid has examined the specimens, and has kindly 

 allowed me to quote the following remarks from his letter giving 

 the result of his examination : — 



* I have looked through your specimens, and find that tbey undoubtedly 

 belong to the Weybourne Crag. The species are the same as those found at 

 Cromer, but the assemblage suggests water a fathom or two deeper, and at the 

 same time slightly more estuarine. Littorina and Bcdamts, which form so 

 large a proportion of the shells at Cromer, are missing ; but so too are the open- 

 sea species which belong to the depth suggested by the rest of the shells. There 

 is nothing to indicate the proximity of any Pliocene deposit other than the 

 Weybourne Crag. 



' The following species are represented : — 



Astarte horeaUs, 

 Astarte compressa. 

 Cardium edule. 

 Cyprina islandica. 

 Mactra ovalis. 

 Mya truncata. 

 Nucula CohholdicB. 

 Tellina haltldca. 



Tellina ohliqua. 



Tellina praitenids. 



Saxicava rugosa. 



Buccinum widatum. 



Natica catena ('!) 



Natica islandica. 



Purjmra lajnlhis. 



Littorina (one small fragment).' 



The bivalves were all common, the univalves all very scarce. 

 The specimens of Mya ti^iincata almost invariably retained both 

 valves, and were found in the position of life. 



EXPLANATION OF PLATES XLVII & XLVIII. 

 Plate XLVIL 

 Plan of Blocks A & B of the Chalk exposed on the shore at Trimingham, on 

 the scale of 144 feet to the inch. 



Plate XLVIII. 

 Plan of Block C, on the same scale. 



