352 Prof. Sedgwick on the Classification of the Strata [May, 



nation seems to prove, that in the structure of the component 

 beds, in the arrangement of the groups, in their order of super- 

 position, and in the suites of organic remains, there is an almost 

 perfect coincidence between the Yorkshire oolite and the coral 

 rag formation in the south-western parts of our island. Indeed 

 the coincidence is much more perfect than one commonly disco- 

 vers in comparing the remote parts of one continuous deposit * 



Sect. 6. — Coal Formation of the Moorlands, <^c. 



With very limited exceptions, the whole cliff extending from 

 the neighbourhood of Filey Bridge to the eastern end of Robin 

 Hood's Bay, and the higher portions of the cliff between Robin 

 Hood's Bay and the extremity of Huntcliff, are composed of beds 

 of shale, sandstone, ironstone, &c. which in their individual cha- 

 racter, as well as in their mode of grouping, very nearly resemble 

 the great coal formations of our island. Very elaborate details, 

 connected with the natural history of these beds, their extent, 

 and their range through the interior of the district, are given in 

 the " Geological Survey of the Yorkshire Coast," p. 79—127. 



The lowest beds of the group described in the preceding sec- 

 tion are succeeded, in the cliffs north of Filey Bridge, and also 

 at Scarborough Castle Hill, by a great bed of shale, which, on 

 first visiting the coast, I considered as the representative of the 

 Oxford-clay. It is, however, in many places subdivided by 

 several beds of sandstone ; and in some places the sandstone so 

 far predominates as completely to alter the character of the 

 deposit, which is too much interlaced with the inferior beds to be 

 properly separated from them.f In short, like the shale of the 



rect account of the localities. Collections formed in this way tend rather to mislead than 

 to assist in the classification of the successive deposits. In several private collections are 

 many beautiful specimens from the oolite near 3Ialton. Some of these are, perhaps, 

 peculiar to the locality, and several of them are not characteristic of the foniiation. I 

 remarked among them two beautiful Ecliinites, of the division Cidaris, Melanin Hea- 

 dingtonitnsis, and Melanin striata, Lima proboscidea, Plagiostoma rigiduni, and 

 many other species which abound in the coral-rag of Wiltshire, Dorsetshire, &c. The 

 reader may select a good list of the fossils of the oolite from the plates and descriptions 

 affixed by Messrs. Young and Bird to the " Survey of the Yorkshire Coast." 



* Mr. Conybeare thinks it probable that the Yorkshire oolite is the prolongation of 

 the great oolite, which may be traced in one continuous escarpment to the south bank of 

 the Humber ; and the map preiixed to the " Outlines of the Geology of England," is 

 coloured on this supposition. The great oolite in Lincolnshire (at least as far as I have 

 examined it) preserves the usual characters, which it exhibits in all parts of its range 

 from the coast of Dorsetshire ; and it seems incredible that this great deposit should in 

 tlie remaining part of its range, through a part of Yorkshire, not only lose these charac- 

 ters, but assume those which belong to a distinct formation. Had I been aware, when 

 I visited the coast, that any question would ever arise respecting the true place of the 

 Yorkshire oolite, I should have visited the foniiation wliich extends from Newbald to 

 the north bank of the Humber. A careful comparison of this formation with the oolite 

 of the Vale of Pickering, and with tlie oolitic terrace of Lincolnshire, would probably 

 settle the question, if the evidence before us be not already considered sufficient for that 

 purpose. 



■f At Filey Bridge, the great bed of shale makes a well-defined boundary between the 



