82 DESCRIPTION OF THE COAST. 



towards the north. The series here exhibited is drawn to scale in the 

 enlarged section. 



a. Represents the rough argillo-calcareous beds, with layers of septariate ironstone, 



full of shells, and interspersed masses of soft large-grained oolite. The upper- 

 most layer is soft and shaly. 



b. The carbonaceous sandstone series. 



1. A regular bluish or yellowish bed, occasionally fissile ; it then contains a 

 few casts of bivalve shells, becomes very calcareous, and much resembles 

 the " roadstone" of Brandsby. 



2. In this layer of sandstone lie equisetiform and other plants, besides large 

 branches of wood. 



3. Mass of carbonaceous sandstone, with irregular interpolations of shale. 



A complete catalogue of the fossils found at the White nab will be 

 given in the latter part of this work. It may be now sufficient to men- 

 tion that gervillias, aviculae, and short thick belemnites are among the 

 most common. 



Proceeding along the shore, we find the calcareous and ironstone beds 

 exposed in broad flat scars at low-water, and extending, with some 

 interruptions, to Ramsden scar, nearly opposite the bathing machines 

 at Scarborough. The lower part of the cliff, from White nab nearly to 

 the Spaw, is kept by the carbonaceous grit, and above, in irregular often 

 grassy cliffs, lie the carbonaceous shale and thin sandstones : the highest 

 point of this inland cliff, opposite Wheatcrofts farm, two hundred and 

 seventy-eight feet high, is capped by the cornbrash and Kelloways rocks. 

 The calcareous and irony strata have their long, straight, intersecting 

 fissures often lined with double laminae or septa of oxide of iron, between 

 which sometimes occurs a white, compact, soft, smooth substance which 

 the Rev. W. V. Vernon ascertained to be a compound of alumina and silica. 

 Exactly similar septa, and occasionally the same aluminous substance, occur 

 in the superincumbent variable bed of sandstone ; and in addition, this 

 bed presents a number of ochraceous belts or zones parallel to the mar- 

 gins of its blocks, thus beautifully variegating the blue or white colour 

 of the stone. 



