•73 



WEALDEN BEDS. 17 



without any of the purple variegated marls. The junction with 

 the liower Greensand can be exposed by digging, as will be 

 described, but the top beds of the Weaklen are not clf^arly seen. 

 Tlie details in the following section are therefore quoted from 

 Professor Judd's paper on the Punfield Formation.* 



Ft. In. 



Lower Greensand. 



Blue paper-shales ------ 



„ " „ light-coloured and pyritic 



Dark-coloured paper-shales (with Cypridea valdensis), and 



several layers of nodular ironstone . - - 



"Beef" ------- 



Limestone, crowded with Cyrena and a few oysters 

 "Beef" - - . - 



Finely laminated pyritic clay . _ . . 



Ferruginous band, almost entirely made up of shells 



(oysters and small univalves) - - -.03 



Other beds of dark blue laminated shales, with occasional 



beds of limestone, imperfectly exposed ; seen to 30 or 40 



The total thickness of the Wealden Shales, as estimated from 

 the breadth of outcrop and the dip, is about 170 feet. 



Tlie same assemblage of fossils occurs here as in Brixton Bay. 

 Fragments of the thin bands of limestone containing Paludina 

 and Cyrena may be found in abundance upon the beach, together 

 with pieces of lignite, while the Cyprids occur in profusion in 

 certain bands of tinely laminated paper-shales. A pelvis and the 

 external metacarpal bone of the right foot of Iguanodon have 

 been discovered in the sandstone below Yaverland Fort.f 



Vertebrae, a femur, and ribs of the same animal are stated bj 

 Mantell to have been found near the same spot. J 



A femur was found also in the low cliff of Weald Clay to the 

 west of Sandown Fort, a part that is now obscured. The beds 

 are stated to have dipped slightly to the west.§ 



It will be observed that, if the sandstone under Yaverland 

 Fort is the same bed that forms Barnes High, the horizon of 

 the Hypsilophodon band is clearly fixed in Sandown Bay ; but no 

 remains of this reptile have yet been discovered. Mantell notes 

 that some " grey sandstone, interspersed with clay," near Yaver- 

 land Fort, " several cones of a plant allied to the Zamia, mixed 

 with fragments of lignite, have been discovered." || 



For further particulars concerning the fossils the reader is 

 referred to the fossil lists on p. 258. 



* Quart. Journ. Geol. Soc, vol. xxvii. p. 220. 1871. 

 t Eev. Dr. Buckland. Froc. Geol. Soc, vol. i. p. 159. 1826-33. 

 X Geological Excursions round the Isle of Wight, 3rd Ed., p. 98. 

 § T. F. Gibson. Quart. Journ. Geol. Soc, vol. xiv. p. 175. 1858. 

 [l Geological Excursions round the Isle of Wight, 3rd Ed., p. 99. 



E 56786. 



