THE COEaLLIAN ROCKS OF ENGLAND. 319 



The beds underlying those above detailed belong to the Lower 

 Calcareous Grit proper, which may be deemed to terminate up- 

 wards with the remarkable series of " ball-beds " so characteristic 

 of Filey and of the coast section generally. 



D. The Lower Calcareous Grit proper. ft. in. 



1 . Soft calcareous sands, with huge doggers, in three or four layers, 



often containing nests of fossils. The fauna of these beds, 

 though scantier, includes some of the fossils of those immedi- 

 ately above (C. 2). Rkynchonella Thurmanni is still tolerably 

 abundant. We noted also, besides some of the usual forms, 

 Irigonia triquetra ? Yon Seeb., Pecten, sp. (cf. vimineus,) 

 Pinna lanceolata, Ostrea solitaria, Collyrites bicordatus — princi- 

 pally towards the base 12-15 



2. The above group is based upon a hard gritty blue rock, divided 



into two beds, which is sometimes rather cherty, and may be 

 distinguished, both on the scar and in the cliff to the westwards, 

 by its mural outline, which is brought into relief owing to the 

 soft nature of the overlying " ball-bed " sands — fossils chal- 

 cedonized* 6 8 



3. The rest of the Lower Calcareous Grit proper consists of hard 



blue siliceous limestones and lines of doggers alternating with 

 softer grits. In many cases the fossils are chalcedonized. 

 Amongst the most noteworthy are Belernnites hastatus, Ammonites 

 perarmatus (rounded, thick-whorled form, with very promi- 

 nent spikes), A. cordatus, Gryfhcea dilatata, Pecten fibrosus, 

 Perna quadrata, Rkynchonella Thurmanni, and Astropecten 

 rectus. The total thickness down to the Oxford Clay is about 40 



The lower part of the Filey section, as far as the top of the 

 " ball-beds," which gives an horizon readily recognized both on the 

 coast and in the interior, is easily correlated with the Lower Cal- 

 careous Grit proper, of which the ball-beds may be viewed as the 

 top. But the various beds which overlie the ball-bed on the Filey 

 promontory can only be satisfactorily correlated after a comparison 

 with the interior, on which subject we must refer to our subsequent 

 remarks. It may be as well to notice here, however, that, as the 

 several formations are traced along the cliff in a direction W.N.W. 

 towards Newbiggin Wyke, the Filey-Brigg calc-grit (B) and the 

 whole of the Upper Limestones (A), crop out and disappear close to 

 Filey Spa. The Lower Calcareous series (C), on the contrary, 

 maintains its thickness and general character ; and its upper beds 

 (C. 1) are becoming so calcareous and oolitic that they, together 

 probably with a portion of the lower part (C. 2), have formerly been 

 extracted for lime. The remnants about the old lime -kilns con- 

 clusively prove that the fauna is that of the series below the Filey- 

 Brigg calc-grit — GervilUa aviculoides, Rliynchonetta Thurmanni, and 

 Acrosaltnia decorata being amongst the most conspicuous fossils. 

 The lithology is equally clear, as also the position of these lime- 



* We are informed by Mr. Fox Strangways that this mural band beneath 

 the ball-beds is very persistent, and, like them, may be traced into the interior 

 where it often forms the cap of the escarpment salients. This bed also forms a 

 prominent feature in the section of Scarborough Castle Hill just under the ball- 

 beds. 



