FossU Remains on the Yorkshire Coast. 231 



tain no remains cf well defined plants ; but near the centre of the series is a seam of inferior 

 coal, about a foot in thickness, which is worked at Cloughton, but only for burning in limekilns. 



The plants of this lo'.ver series of carboniferous shale, except when found in ironstone, are far 

 from being so beautiful and well preserved as those in the upper shales ; from which they also 

 differ in tlie greater abundance of Pterophyllum minus, Otopteris acuminata, Sphenopteris hymeno- 

 jihylldides, and the deeply lobed variety of Cyclopteris digilata, and are apparently characterised 

 by Pterophyllum pcctino'ides, Equisetum laterale, Zamia lanceolata, and the Ttjmpanophora of 

 Lindley and Hiitton. 



The thick beds of sandstone may be readily traced along the shore, but the other portions are 

 very variable. The sandstones are generally micaceous and hard, but split readily, and are exten- 

 sively used as flngs. As building stones they are much inferior to many of the beds above the 

 great oolite. 



We will now proceed to describe 



The Great or Bath Oolite. 



The lithological characters or fossils of this formation vary very little to the 

 north of the White Nab, near Scarborough, but to the south, a striking- 

 change occurs, which will be described in its proper place. We will first 

 examine the sections at Cloughton Wyke, and the While Nab, where the 

 great oolite presents the following general arrangement. 



a. The lowest bed, a hard blue limestone 14 to 20 feet. 



6. Hard, blue, tine-grained oolite, sometimes ironshot . . G 



c. Hard, blue clay, often much tinged with iron 2 



d. Nodular ironstone, six inches to 1 foot. 



e. Clay 1 



/. Layers of nodular ironstone and argillaceous oolite .. 3 feet. 



(a.) No fossils have yet been discovered in the lower and middle portions 

 of this division, but towards the upper, I have found a species of Ostrea, 

 Amp hide sma decurtatum, Mi/a calceiformis, and an undescribed Ammonite; 

 and the top of this bed contains Belemnites compressus, B. Aalensis, Me- 

 lania Heddingtonensis, Amphidesma decurtatum, Serpulce ; and in a layer 

 between this bed (a) and the hard blue, fine grained oolite (6), are found 

 large tuberculated spines of a Cidaris. 



Of the Belemnites, the species which I consider to be the B. compressus 

 of Sowerby, not Voltz, is occasionally twenty inches in length, and about two 

 in diameter ; and the diameter of the other, B. Aalensis, is three inches, but 

 the length is not more than seven. The spines of the Cidaris are sometimes 

 five inches long, and about the diameter of an ordinary goose quill. Though 

 they are not rare, I have found no traces of the Cidaris itself. 



