140 OEOLOGY OF THE ISLE OF WIGHT. 



mile north-east of the farm. Here the following species were 

 collected by J. Ehodes, the fossil collector of the Survey : — 



Chara. 



Cyrena obovata. 

 Cytlierea incrassata. 

 Tellina, sp. 



Ancillaria buccinoides. 

 Buccinum labiatum. 



Ceritbium elegans. 

 Hydrobia, sp, (young). 

 Melania muricata. 

 Melanopsis subfusiformis. 

 Natica labellata. 

 Nematura parvula. 

 Neritina concava. 

 Pleurotoma headonensis. 



The Ceritliium is very abundant, in a shelly sand, and there is 

 also a bed of clay full of Cytlierea, but it is difficult to make out 

 the true succession. 



Further north, about 8 chains south of Eades Farm, a ditch 

 section shows clay full of Potaniomya grcgaria. On the opposite 

 side of the stream fossils are ploughed up abundantly in the 

 fields. Those collected by J. Rhodes were Cyrena deperdita, 

 C. ohovata, Hydrobia Chasteli, Melanopsis carinata, Melania 

 muricata, Neritina concava, Nematura parvula, and Planorbis. 

 There is nothing among these to show to what part of the Headon 

 Series this shelly clay belongs. 



From Newbridge eastward to the Medina, the beds are nearly 

 vertical. Not a single section of the Headon Series is now 

 visible there. 



At Newport, though the beds cannot be examined at the surface, 

 the whole thickness of the Upper and Middle Headon strata 

 seems to have been penetrated in a well at Messrs. Mew and 

 Company's Brewery {see Appendix, p. 305). It is not easy to fix 

 the boundary between the Osborne and the Headon Beds, but 

 taking it as occurring at 259 feet from the surface, we have thick- 

 ness of 189 feet down to the sand which yielded water. Of the 

 189 feet of Headon Beds, at least 82 feet should be referred to 

 the Upper Headon, and the remainder to the marine Middle 

 Headon. Any attempt to correlate the minor subdivisions 

 would be unsafe, for the samples preserved were small, and the 

 thickness of the different beds appears to have been greatly 

 increased by lateral pressure. Within a few hundred yards of 

 this well lies the area of sharpest folding. 



At West Cowes another well has been sunk to supply the town 

 {see Appendix, p. 313). Here again the boundary between the 

 Osborne and the Headon Series is very difficult to fix, but it 

 seems to lie about 268 feet from the surface. At 365 feet, i.e., 

 97 feet below the top of the Headon Series, the shelly " Venus 

 Bed," commences, and from a sample of clay brought up from that 

 depth the following species were obtained: — Cytlierea incrassata, 

 Cyrena, sp., Buccinum lahiatum, Natica. labellata, Nematura. 

 parvula, and an otolith of fish. From 375 feet a sample of green 

 clay contained Natica and indeterminable shell fragments. From 

 the spoil heap at the well a considerable number of species were 

 obtained, and though the exact depth from which ihey came could 

 not be fixed, they certainly belong to the clays at about 41-1 feet. 

 The species collected Avcrc :— 



