144 Mr. Williamson on the Distribution of 



stones to the Spa at Scarborough, On the northern side of Scarborough Castle 

 the upper beds of the stratum dip under the cornbrash, and consist chiefly of soft 

 yellow sandstones, but near Scalby Beck a mass of soft blue clay intervenes ; 

 below this a variable series of sandstones and clays occupies the remainder of the 

 coast to Cloughton Wyke, where the lower beds again repose on the Bath oolite. 

 After capping the cliffs of Stainton Dale, they do not reoccur on the sea-coast. 



These beds are certainly much thinner to the south than to the north of Scar- 

 borough ; and from their changeable character, and the comparative absence of 

 organic remains, but three divisions can be established, and these perhaps not very 

 distinctly. Mr. Phillips, in his ' Geology of Yorkshire,' vol. i. p. 40, remarks, " the 

 lower part consists chiefly of thick irregular strata of sandstones. Above is a thick 

 deposit of dark- and light-coloured shale, with alternations of thin sandstones." 

 This was written under the impression that the argillaceous deposits of Gristhorpe 

 were to be considered as the top of this series. A thick mass of rather compact, 

 light yellow sandstones reposes on the Bath oolite ; then a series of shales, 

 occasionally changing into soft clays, and these are surmounted by another series 

 of yellow sandstones much thinner than the lower group. 



The two principal localities for fossils are on the north side of Scalby Beck (near 

 Scarborough), where, not far from the top of the lower division of sandstones, the 

 beautiful Cyclopteris digitata of Lindley and Hutton (not of Brongniart) occurs ; 

 and still lower in the series, in Burniston Bay, a layer of ferruginous sandstone 

 contains Pecopteris Murrayana, Otopteris ohtusa, and an unfigured Carpolithes ; a 

 considerable quantity of imperfectly preserved fossil wood occurs north of Scar- 

 borough Castle. In the lowest beds, south of the Spa, I have observed traces of 

 Cycadean and Equisetiform plants, as well as quantities of carbonized wood in 

 small fragments. The ironstones scattered through the stratum generally contain 

 veins of the Scarbroite of Harcourt*. There is no doubt that further investigation 

 will materially increase this list of fossils. I have found the Cyclopteris in the lower 

 sandstone and shale, whilst Brongniart's species, which is less deeply lobed and 

 more palmate, seems confined to the deposits of Gristhorpe Bay. The Otopteris 

 I have not seen from any other stratum ; but so little is yet known of the fossil 

 remains of these sandstones, that the above cannot be called characteristic. 



Cornbrash. 



This formation first rises from the foot of Gristhorpe cliff, at " Pudding Hole." 

 By the fault at RedclifF it is thrown down to the shore. Near the northern ex- 

 tremity of Cayton Bay it is again observed for a limited extent, but it is soon lost 



* Annals of Philosophy, March 1829. 



