Vol. 65.] GEOLOGY OF THE NEIGHBOURHOOD OF SEAFORD. 445 



cor-anguinum, as this is one of the rare cases in which the fossils 

 of the inland outcrops are not apparently in strict agreement with 

 those of the cliff-section. Only the higher ground due south of 

 Friston is occupied by the Marsupites-Zone, which does not, there- 

 fore, show itself in the cliff-section east of Crowlink. 



Distinct evidence of the Marsupites-Zone is also found in the hill 

 above Exceat New Barn, where Uintacrinus, Terebratulina Roivei, 

 and several specimens of the large flat form of Rhynchonella 

 plicatilis were found. A pit here is probably near the top of the 

 Uintacrinus -Hand, for just over the ridge, in Limekiln Bottom at 

 uearly the same level, plates of Marsupites occur in fair quantity, 

 immediately below the 300-foot contour. Several old pits occur 

 round Limekiln Bottom, and I was told that lime-burning was 

 formerly carried on there. Most of these pits extend downwards 

 into the Marsupites-Zone, but they are now largely overgrown. 



It is easy to link up the evidence thus obtained with that 

 of the cliff-section. Although the northern edge of the plateau is 

 less satisfactory from the point of view of exposures, there is 

 sufficient evidence to show that the Marsupites-Zone occupies all 

 the higher ground between Friston and Cliff End. There is, how- 

 ever, a thickness of Chalk above the lowest part of the Uintacrinus- 

 Band, which is too great to be thus accounted for. Moreover, above 

 the level of the highest occurrence of Marsupites there is distinct 

 evidence of the passage-beds characterized by an abundance of 

 Ostrea ivegmanniana, bryozoa, and Rliijuclionella plicatilis. There 

 still remains a thickness of nearly 50 feet on the highest part of 

 the plateau, which must therefore belong to the zone of Actino- 

 camax quadratus. Thus this plateau is capped bj- Marsupites- 

 Chalk, with a thin covering of A. -quadratus Chalk at the western 

 end. The beds lie with so slight a westerly inclination that they 

 appear to be nearly horizontal. The actual change in level of the 

 Uintacrinus-Bimd between Crowlink and Cliff End, a distance of 

 about 2 miles, is approximately only 100 feet, giving a very small 

 angle of dip in this direction. 1 



The lower slopes between Cliff End and Exceat Farm are in the 

 zone of Micrasier cor-anguinum. A pit near the sharp easterly bend 

 of the river, close by the Farm, yields very characteristic fossils, 

 including the name-fossil in abundance and large valves of lno- 

 ceramus cuvieri. The flint-lines are nearly horizontal here and 

 elsewhere along the valley on this side of the river, as far as Cliff 

 End. This approximate horizontality of the beds on the east side 

 of the Cuckmere is important to note, in view of what follows. 



Proceeding to the west side of the Cuckmere, some initial difficulty 

 was experienced in finding an inland outcrop of the Marsupites- 



1 The cliff-section in Dr. Howe's paper, drawn by Mr. C. Davies Sherborn, 

 indicates a slight rise between Crowlink Valley and Cliff End, and there 

 may be a transverse undulation in addition to the general dip. To this further 

 reference is made on p. 453. 



