fitton's section at atherfield. 311 



sand of the Gryphsea beds beneath, Nos. 13 and 36*. b. The upper 

 part is reddish and brown sand (3 ft. 6 in.). 



44. About 12 feet of sand, alternating with thin beds of dark 

 greenish or black coherent mud, or clay mixed with sand. One such 

 bed about a foot thick was found by Captain Ibbetson to contain 

 fossils : in another about 6 feet above it, of 8 or 9 inches, I found a 

 Panopsea, and other species, like those of the Perna clay No. 1, at 

 the bottom of this section. 



Fossils of Nos. 41 to 44. 



In 41, 42 and 43, very indistinct traces only of fossils have been 

 found. 



In 44, — Panopsea plicata, Sow. Corbula striatula, Sow. 

 mandibula, Sow. Lingula truncata, Sow. 



XIV, Ferruginous Bands of Black-Gang Chine f. — iVb. 45. a, b, c. 



This group is one of the most remarkable in this section, being, 

 here, the limit between the fossiliferous beds of the series, and those 

 in which fossils have as yet been extremely rare. This contrast is 

 probably no more than local ; but a similar group is found in nearly 

 the same part of the series in so many other distant points as to 

 deserve especial notice. It rises on the shore about midway between 

 Rocken End and Black-Gang Chine, and can be traced continuously 

 to Walpen High Cliff, where its decomposition is very favourable to 

 the extraction of the fossils ; and though no more than vacant moulds 

 of shells, these are so well characterized, that the species can be iden- 

 tified in several cases with those of the Perna group, at the very 

 bottom of this section. 



The species here are the same also with those found in the cor- 

 responding part of the lower greensand at Parham Park and other 

 places in Sussex, and near Sandgate in Kent J ; the fossiliferous 

 masses are not distinguishable from those of Horseledge near Shank- 

 lin, where in fact the beds are a continuation of those at Black-Gang 

 Chine. 



The group 45 may here be subdivided as follows — the total thick- 

 ness being about 20 feet : — 



* See hereafter, p. 318, for a list of the species found near Shanklin, in what 

 seems to be the corresponding portion of the series there. 



t Cascade of Black-Gang Chine (1843) : — 



Height of the spot where the fall begins, above that where ft. in. 



the water springs off from the cliff 8 



Vertical fall of water (62 ft. 10 in.) 63 



Bottom of the fall, above high-water mark..... 20 



Height of summit above high-water mark 91 



X Some very remarkable specimens from the site here referred to were 

 obtained by Mr. Simms during the excavation of the railway tunnel at Salt- 

 wood, near Hythe: — see Proceedings of Geol. Soc. iv. p. 208, and Journal, 

 vol. i. p. 34, &c. 



