120 Mr. D. Sharpe on the Geology of 



Limestone, very sandy 3 feet. 



Marl 2 — 



Sulphureous marl 2 — 



Lignite, very sulphureous 1 — 



Sulphureous marl 4 — 



Marl of various colours 20 — 



Limestone, alternating with sandstone. 



The coarse sandstones of the lower division of the formation. 



We were told that the lignite may be traced along the cliff northward for several miles to Aganheira, 

 and that there it is thicker and of better quality. 



To the eastward of Cezimbra a similar section of sulphureous marls, accompanied by lignite, sand, sand- 

 stones and limestones, is exposed on the beach : the beds of lignite are not more than half an inch in 

 thickness, and were it not for the abundance of sulphur, might easily be overlooked. 



The resemblance of the sulphureous deposits at Cascaes and Cape Espichel is so great, that they must 

 be considered as identical, although at Cascaes they occur above the calcareous beds, and at Cape Espi- 

 chel among them : this lessens the importance of the divisions of the formation. 



The tepid springs of Estoril, near Cascaes, rise so close to the sulphureous beds, that the water probably 

 derives its virtues from them : the celebrated hot springs of Caldas da Rainha in Estremadura rise through 

 the upper division of this formation, and may possibly owe their sulphureous qualities to similar beds. 



Gypsum has been worked in some quantity near the village of Sta Anna, three miles from Cezimbra. 

 I did not examine the spot, but have reason to believe that it is in immediate connexion with the sul- 

 phureous marls. 



Orgayiic Remains. — The following fossils have been found in the calcareous division of the formation : 



Terebratula biplicata (var. b.), Sow. Min. Con., 90, f. 2 and 3, a shell of our green sand. 



Perna rugosa, Goldfuss, t. 108, f. 2, found also " in stratis arenaceo-oolithicis Westphaliffi." 



Trigonia (Lyrodon, Goldfuss, t. 136, f. 5, e,) figured by him as a variety of T. literata, from which it 

 is apparently distinct. 



Astreea, two species, one of which bears a strong resemblance to a coral common in the coral rag of 

 Steeple Ashton. 



3. Espichel Limestone. (PI. XIV. and PI. XV. Sect. 1, 2, 4, 5, 7, 9, 12, and 13.) 



Near the Cintra hills the red sandstone rests upon a calcareous formation of very- 

 considerable thickness, to which, from its also forming the point of Cape Espichel, 

 I give the name of Espichel limestone. Its principal deposit is a fiat barren tract, 

 which encircles the whole range of the Cintra hills, and attains its greatest breadth 

 where the road from Lisbon to Cintra crosses the Charneca, but in other parts it is 

 of little extent. It rests throughout conformably upon the slate-clay, dipping from 

 the Cintra hills as from a centre at angles varying from 20° to 75°. Tliere is an 

 exception to this dip on the north of Cintra, where a line of disturbance, ranging 

 east and west from Algerao to the coast, has raised some of the beds into a saddle, 

 and formed two parallel faults. This dislocation may be seen to the north and north- 

 east of the town of Cintra, and in the cliffs near the Praia de Macaas (Sect. 2, 4 

 and 5), but it is concealed near Colares by the red sandstone which overhes part 

 of the formation. 



