Fossil Remains on the Yorkshire Coast. 223 



and Saltburn, where large blocks of the sandstone have fallen from the 

 cliffs. 



Above these sandstones is a layer of detached, irony and calcareous nodules, 

 very rich in fossils ; the principal being. Ammonites Clevelandicus, A. Stokesii, 

 Turbo undulatus, Isocardia lineata, Cardium multicostatum, Corbula cardi- 

 oides,Amphidesma recurvum, My a V. Scripta, M. literata, Terebratula bidens, 

 T. subrotunda, T. tetraedra, T. triplicata. 



Of these, Ammonites Clevelandicus, Cardium multicostatum, Isocardia lineata, and Terehratula 

 tetraedra, appear to be the most abundant. 



Eight or ten feet higher, is a series of beds from twelve to fourteen feet 

 thick, consisting of arenaceous, blue shales, divided by bands of ironstone. 

 The shales are filled with a profusion of fossils in a fine state of preservation, 

 but difficult to extract, owing to the fragile nature of the shell, which is easily 

 separated from the cast. The following is a list of the species : Pecten cequi- 

 valvis, P. sublcevis, Avicula cijgnipes, A. incequivalvis, and Plicatula spinosa ; 

 also two species of Belemnites. 



The principal locality for these fossils, is under the signal cliff at Staithes, 

 where the shales are near the beach and better exposed than elsewhere. 



In the uppermost bed of ironstone, dividing the marlstone from the upper 

 alum shale, the jimmoniles Haivskerensis is found, at the south point of Runs- 

 wick Bay, and associated with it, at Skinningrave, is a small fossil, apparently 

 a Trochus. 



3. Upper Lias or Alum Shale. — This division consists of three very distinct 

 deposits, which are extremely persistent. 



a. Lowest part, soft shale 1.5 to 20 feet. 



b. Hard shale, differing from the preceding in being much more tenacious, 



and in the laminae breaking into larger fragments, about 30 



c. Shale resembling the lowest part, being soft and rubbly, and breaking into 



very small fragments, average thickness about 130 



Though well distinguished by lithological structure, these deposits are 

 much better characterized by their fossils. 



(a.) Near the junction of this deposit with the marlstone, Beletnnites co?n- 

 pressus occurs in considerable numbers, in a thin layer, especially at Runs- 

 wick Bay ; and at the top, almost immediately below the hard seam (6), is a 

 layer of argillaceous nodules, which is first seen about a mile north of the 

 village of Staithes, and again under the cliffs at Lylh. At these places the shale, 

 on the Scar, is completely studded, for forty or fifty yards, with round con- 

 cretions, each containing either one or two Ammonites annulatus, orthealveo- 



VOL. V. SECOND SERIES. 2 G 



