NORMAN UPPER GREENSAND OF ISLE OF WIGHT. 483 



ness as that above, the last resting upon the Cock-bed," of about three 

 or four inches thick. 



I consider, from my own observations, that all the fossils of the two 

 upper beds, the Phosphatic " and Chloritic " marls, ought, with few 

 exceptions, to be referred to the chalk-marl ; but not those below this 

 very clear line of demarcation. The fire- stone, when first quarried, 

 is of a soft texture, but hardens by exposure to the atmosphere ; it 

 is fire-proof, and used by masons in fixing grates, for oven-bottoms, and 

 other purposes where endurance of heat is an essential quality. It was 

 from the beds of rag in this group that the fossil bone of a terrestrial 

 animal, described at page 179 of Mantell's ''Excursions round the Isle 

 of Wight,"* was obtained in a quarry (now closed) near the Bonchurch 

 Hotel. This relic is now in the possession of — Hanbury, Esq., and 

 the writer of this has seen a good wheelbarrow-full of bones of an animal, 

 apparently Saurian, dug out of the same quarry; but from their 

 decomposed state, these were too friable to permit the preservation of a 

 single specimen. A few teeth were secured, but, owing to this cause, 

 they fell, shortly afterwards, to pieces by exposure to the atmophere. 

 These remains were obtained from the lowermost bed of the "Phosphatic 

 Greensand." 



6th. The next beds in descending order are important ones in an eco- 

 nomic point, from their great utility as a building-material, and the 

 consequent demand for them for such purposes. Their place in the 

 series of deposits forms a well-marked epoch or line of demarcation in 

 the history of the " Upper Greensand ; " they may be divided into five 

 sections : — The first is a bed of grey sandstone, about one foot thick, 

 called by the quarry men the " Top Bed," succeeded by a layer of rag- 

 stone from eight to nine inches thick ; thirdly, another bed of sandstone 

 of about the same thickness as the rag ; fourthly, a thick bed of freestone, 

 often considered to be analogous to the Portland building- stone, but 

 erroneously so, being different in composition and mineral character, 

 and evidently consisting of a mixture of grains of silex and, probably, 

 of iron, cemented by carbonate of lime ; the roe-like particles of the 

 Portland-stone being really wanting.f The fifth bed consists of the 



^ Page 247, Editions of 1847 and 1851. 



t I have mentioned this because of a popular error that exists amongst the 

 masons and others of this locality, namely, of the identity of the free-stone with 

 that of the Portland rock ; an error which, of course, no geologist would fall 

 into. 



