Or THE UPPER CKETACEOUS IN WEST SUFFOLK AXD NORFOLK. 557 



We think that there can be no doubt about this glauconitic marl 

 being the representative of the Cambridge Greensand (Chloritic 

 Alarl), and by adding the thickness shown in the boring to that of 

 the chalk between the quarrv-floor and the base of the Totteruhoe 

 Stone, we get 75| feet as the total thickness assignable to the 

 Chalk-marl. 



The Totternhoe Stone has no definite top or base, even the "brassil'"- 

 like line of nodules being rather at the top of the mottled band than 

 at the base of the grey chalk ; this mottled band evidently consists 

 of two distinct kinds of material, and looks as if it had been originall}" 

 a layer of white chalk in which pipes and hollows had been excavated 

 and filled up with the grey material : its depth is about 12 inches ; 

 it and the grey stone above split together into large blocks. jSTone 

 of the chalk in this quarry exhibits any distinct planes of bedding, 

 but the band of Totternhoe Stone is fairly conspicuous on account 

 of its grey colour. 



The ridge formed by the hard beds of the Chalk-marl and 

 Totternhoe Stone runs for some distance beyond Stoke Perry, its 

 strike being to the N".W. ; but near Wereharn it is capped and 

 partially concealed by thick deposits of gravel. About a mile north- 

 west of Wereharn, and half that distance from West Dereham Church, 

 there is a quarry exposing the following section : — 



feet. 



Soil and chalk -rubble 3| 



Rather dark grey thin-bedded gritty chalk 3 



Yellowish-grey marly chalk with many yery hard. 



lumps on the weathered surface 8 to 12 



The lower beds resemble the hard Chalk-marl of Stoke ; but 

 though the bed above had some resemblance to Totternhoe Stone, 

 there were no signs of the " brassil "-like nodules which so invariably 

 occur near its base. We think therefore that it is probably one of 

 the harder beds of the Chalk-marl like those passed through in the 

 boring at Stoke. 



At Crimplesham the Chalk-marl passes beneath the Boulder-clay, 

 by which it is entirely concealed for a space, and the next exposure 

 seen was in a small quarry at Shouldham by the roadside south of 

 the church. Here about six feet of tough yellowish-grey chalk in 

 lumpy and irregular beds overlie two feet of soft grey shaly and 

 silty marl, which is full of small green glauconite grains and con- 

 tains many small green-coated phosphatic nodules ; Avicula gry- 

 phceoides is abundant in this glauconitic marl, and we have no doubt 

 that this bed is identical with that found at the bottom of the boring 

 at Stoke. We could not reach its base on account of the water 

 which stands iu the quarry ; but the standing water testifies to the 

 existence of impermeable clay below. Shouldham itself stands on 

 the clay flat, which is, however, much narrower than at West 

 Dereham. 



This Glauconitic l[arl is very similar to some varieties of the 

 material which forms the basement- layer of the Chalk-marl near 

 Q. J. G. S. Xo. 171. 2 u 



