HEADON BEDS. 137 



met with would have necessitated the use of lining tubes if it were 

 to be continued. North of this point the dip quickly carries the 

 base of the Headon Beds below the sea level. 



Returning to the western end of Hciidon Hill we find a thick 

 limestone forming the top of the cliff. The position of this lime- 

 stone is close to the base of the Upper Headon Beds, and it over- 

 lies a series of marine clays and sands full of Cerithium, Ostrea, 

 and Cythcrca. These marine beds belong to the Middle Headon 

 Series, but unfortunately they are not at the present time clearly 

 exposed, except at the two ends of the Hill. 



From this point the marine beds are almost entirely hidden by 

 landslips for about a mile but the limestone can be followed, and 

 in a similar position below it at the north-eastern end of the hill 

 the marine beds again occur. Part of these can be well examined 

 at the present time, though they are not easy to find unless one 

 has first identified the thick Limn£ean limestone. 



Messrs. Keeping and Tawney give a carefully measured section 

 at this point, which is here reproduced. Fig. 36 {see page 136). 



The base of the thick Upper Headon Limnasan limestone at 

 the point where it leaves the coast is about 120 feet above the 

 sea, and at the north-eastern end of the Headon Hill outlier it 

 has fallen to about 110 feet. Crossing the small valley which 

 divides Headon Hill from a lower hill nearer Middleton, we find 

 the thick limestone at a height of 130 feet. From this point it 

 falls in less than a quarter of a mile to about 110 feet. Then 

 it flattens for another quarter of a mile, and remains at the 

 same level at the northern extremity of the outlier near Amos 

 Hill. 



Returning to the coast we find the Oyster Beds in the marine 

 Middle Headon Beds about 95 feet above the sea at the point 

 where the cliff becomes low near Widdick Chine. Half a mile 

 to the north-east there is a small hill on the northern side of 

 Weston Chine which just reaches 100 feet. The upper part of 

 this hill is occupied by a brick-yard, and 7 feet down in the clay, 

 i.e., at about 93 feet, the Oyster Bed is again found. It is full of 

 fossils, but they are not well preserved ; the species noted were 

 Ostrea velata, Cythcrea incrassata, and Buccimun lahiatum. 

 Thus the same flattening of the beds for a short distance occurs 

 here which we have already noticed in the limestone. 



Still further inland, to the north-east, the Oyster Bed is ao-ain 

 met with in a large brick-yard near Amos Cottage. Here the 

 height is about GO feet. In this brick-yard the fossils are all in 

 the state of casts, and only Ostrea velata and Cythercn incrassata 

 could be determined. 



Returning to Totland Bay, we find the dip to become hio-her 

 and the marine beds again to strike the cliff" a ie^^ chains north 

 of the Coast Guard station, at a height of about 80 feet. From 

 this point these beds can be followed continuously, exccj't in the 

 parts under Warden Battery, and over short distances where the 

 face of the cliff is obscured by talus. A few yards north of How 



