416 REPORT— 1887. 



Very few plants are known from the Upper Headon, but a band of 

 clay ironstone above the limestone, also found by Mr. Keeping, occasion, 

 ally contains beautifully preserved leaves. Examples of these are in the 

 museums at Cambridge and York. It is some years since any have been 

 found, and we have failed to meet with them lately, though we have often 

 made special search. 



The Osborne marly clays have undergone a chemical change, leaving 

 them ' mottled,' which has seemingly obliterated all traces of plants, if 

 any existed, though nucules of Chara are met with in the limestones of 

 this, as well as of the Bembridge series. Our work was therefore almost 

 entirely in the beds above this horizon. 



The grant was handed to Mr. Keeping, who commenced work on May 24 

 in Parkhurst Forest. The Hamstead series has, it is well known, an ex- 

 tremely limited outcrop. The freshwater beds are succeeded by a brackish 

 series, ultimately passing into marine beds, and occupying successively 

 more and more restricted areas, until on the very apex of Hamstead Hill we 

 find what is evidently the basal bed of a marine series of some importance. 

 Most of the fossils have disappeared by weathering owing to proximity 

 to the surface, but a very distinct and almost gigantic oyster, 0. callifera, 

 often bored by Lithodomus, has withstood the atmospheric action. The 

 formation, being higher than anything in England beneath the Pliocene, 

 has always attracted interest, and the importance of finding other and 

 better outcrops has thus appeared very great. It seemed highly probable, 

 looking at the contour of the land and observing the dip inland at the 

 cliff line, that such would be found in the high ground of Parkhurst 

 Forest. Indeed, that most accurate observer, the late Mr. Godwin -Austen, 

 stated (Mem. Geo. Surv., Isle of Wight, 1856, p. 37) that specimens 

 of the characteristic Ostrea callifera had been found on the surface there. 

 Keeping had also found, rather low. down, some shelly matter which he 

 took to be the debris of marine shells. We accordingly commenced by 

 sinking a pit in the high ground towards the north of the Forest, known 

 as Mark's Corner, choosing a disused gravel pit within fifteen or twenty 

 feet of the summit in order to avoid the labour of digging through the 

 drift. After getting through the base of the gravel and clay to a depth 

 of twelve feet we came to unweathered laminated beds with partings of 

 white sand, containing Paludina, the small globose fruits so abundant in 

 the Hamstead series, and remains of freshwater fish. These clearly 

 belong to the freshwater series of Hamstead, and we consider their 

 horizon to be about twenty-five feet below the Corbula suh-pisum beds of 

 Forbes. The next essay made was on the Signal Hill, a mile to the 

 South, and also in a gravel pit about twenty feet fi-om the summit. Here 

 we found mottled green clay ten feet thick under five feet of gravel with 

 Paludina, Planorhis, JJnio, Chant., and a fragment of Emys. These also 

 were clearly in the freshwater series and correspond with the moftled 

 bed about fifteen feet below the Corbula bed. As these are the highest 

 points of the Forest it thus seems perfectly safe to conclude that no 

 higher beds occur in Parkhurst Forest than at Hamstead, and that the" 

 latter presents by far the best development of them. 



The escarpment forming Hamstead Cliff is cut through a hill 210 

 feet high, the crown of which has already disappeared. The highest 

 marine beds are confined to the apex of this hill and cannot have more 

 than a few superficial yards extent, the rapid weathering threatening in- 

 deed to remove every vestige of them before many generations shall have 



