162 



GEOLOGY OF THE ISLE OF WIGHT. 



tufaceous concretionary portion is a curious layer or old surface, 

 in which He the remarkable bodies regarded by Mr. Edwards as 

 turtle's eggs." 



Besides the fossils mentioned, Helix omphahis and H. tropifera, 

 Pupa perdentata and P. oryza, Clausilia striatula, Cyclotiis cinct7is, 

 and Succinea Echvardsii, were all collected by Prof. Forbes and 

 Mr. Gibbs in this prolific locality, the Clausilia and Cychtus 

 being by no means uncommon. Although diligently searching for 

 many days these observers met with no remains of vertebrata. 



The following list of shells procured by Mr. William Cotton of 

 Freshwater, during the course of a single morning, will show the 

 variety and abundance of the fossils contained in the limestone 

 here : — 



Fossils from tke Bemhridge Limestone of Sconce. 



No. of Specimens. 



Achatina costellata (Fig. 54) - - - - - 1 



Helix globosa ? - - - - - -3 



„ vectensis, var. depressa - - - - - 8 



„ D'Urbani - - - - - - 12 



„ occlusa - - - - - - -4 



„ tropifera - - - - - - 1 



„ (or Paludina) carinata, [probably Paludina angulosa] 5 



Clausilia striatula? (young) - - - - - 2 



Planorbis obtusus - - - - - - 3 



„ discus 



„ oligyratus (young) - - - - - 25 



Limnsea longiscata, var. 

 „ slender var. small. 

 „ ? large bodied var. 



Cyclotus cinctus _ - - - - 6 



„ nudus - - ■• - - - 1 



Bulimics ellipticus, Achatina costellata, and Helix globosa, are 



all large conspicuous species. Paludina. angulosa and Achatina 



costellata. (Fig. 54) are the shells especially sought 



Fig. 54. for by the native collectors ; but good specimens 



Achatina ^^^^^ *^® shell preserved ai'e rare. The blocks 



which have fallen from the crest of the hill 



are crowded with specimens of Planorbis and 



Limncea, and occasionally Helix, the most 



common being Helix U'Urhani, H. occlusa, and 



H. vectensis. 



The Bembridge Limestone of Sconce descends 

 below the 50-foot contour at its eastern end, and 

 the small outlier further east nearly touches the 

 25-foot line. Continuing the dijj shown by these 

 outliers, we observe that the limestone ought to 

 plunge beneath the sea within a short distance. 

 We accordingly find an isolated rock at a quarter 

 of a mile from the shore off' Norton. This is 

 known as Black Rock. It is only visible at ex- 

 tremely low spring-tides, and we have not been 

 able to examine it, but have been told that it 

 consists of a hard freestone. 



costellata, Sow, 



