GREEN OR CHLORITE SAND. 77 



Pevensey Levels *. This substance is of a dark chocolate colour, 

 is easily scraped with the knife, and emits a strong bituminous odour. 

 Exposed to the action of the hydro-oxygen blow-pipe it burns with a 

 bright flame, and fuses into a steel grey enamel f. 



On the coast near Southbourne, the sand bassets out from beneath the 

 chalk marl, and forms a low crumbling cliff, which extends but a short 

 distance to the north, and then disappears beneath the alluvium of 

 Pevensey Levels. 



This sand is of a grey colour, and is thickly interspersed with particles 

 of the green substance previously described ; it also contains specks of 

 mica. Where in contact with the superincumbent bed of chalk marl, it 

 becomes intermixed with that deposit, and some of the fossils pecuhar to 

 each, are associated together at the line of junction. In a hasty visit to 

 this spot, in the summer of 1818, I collected several species of Inocera- 

 mus, Pecten, Plicatula, Terebratula, NautiHtes, Ammonites, Cirrus, a few 

 Spongitae, and other zoophytes. Few of these, however, are decidedly 

 analagous to the species which occur in the green sand of Wiltshire : but 

 partake more of the characters of the chalk marl fossils ; indeed it is ob- 

 vious, that the strata in this place are not exposed to a sufficient depth, 

 to allow of our obtaining the usual productions of the former. 



From what has been previously remarked, the general agreement 

 between the fossils of the green, grey, and ferruginous sands of Sussex, 

 and those of the chlorite sand of Wiltshire and Devonshire, is however 

 sufficiently estabhshed. The TrigonicB, Cucullea, RostellaricB, Pectinites, 

 Terehratulce, &c. are common to each county, but the mode in which these 

 remains are preserved differs remarkably. In Wiltshire, the shells have 

 undergone but little change; in Devonshire, they are converted into chal- 



* This bed was worked by the Romans, who employed it in the construction of part of 

 Pevensey Castle. In the alluvial clay near Chilley, Mr. Rand discovered the remains of a 

 Balista, and a considerable number of enormous balls of bituminous sandstone ; the latter wei-e 

 in all probability intended to supply the engine, which (as is well" known) was employed for 

 hurling large stones. 



t A specunen analysed by my brother, contained 15'4 per cent of bitumen. 



