1826.] tuJiich appear on the Yorkshire Coast. 351 



Having thus endeavoured to fix the general characters of the 

 coral rag formation, we may now proceed to examine the nature 

 of the oolitic deposit on the Yorkshire coast and in the vale of 

 Pickering. The lower part of this deposit consists principally 

 of beds of calcareous grit and sandstone, in mineralogical struc- 

 ture, perfectly identical with the lowest groups of some of the 

 sections of the coral rag described above. At Filey Bridge, 

 Scarborough Castle Hill, and other locahties, we meet with beds 

 aggregated into irregular branching and imperfectly cylindrical 

 masses, exactly resembling those at Weymouth.* Associated 

 with the same beds are many fossils both in their state of pre- 

 servation and in their species identical with the fossils in the 

 bottom group of the Weymouth section. Out of these may be 

 enumerated a large flat oyster, ostreagregaria, ostrea Marslm(>), 

 gryphea dilatata, trigonia clavellata, pecten (the small species 

 which abounds at Weymouth), and the small echinus {cli/peus 

 clunicularis), &c. Sec. 



In every place where the formation is well exhibited, there is, 

 immediately over the calcareous grit, a group of beds of ooliticlime- 

 stone more or less mixed with imperfectly coherent beds containing 

 comminuted fragments of the ostrea gregaria, trigonia clavellata, 

 perna aviculoides, and various other fossils. These beds in mine- 

 ralogical character are perfectly identical with the coral-rag 

 oolite, and present examples of all its varieties. . For very com- 

 plete details respecting the two preceding groups, I must refer 

 to the " Survey of the Yorkshire Coast," p. 61 — 79. 



The sections near the coast do not in general exhibit any 

 important deposit superior to the preceding group. Near the 

 village of Ayton, there is, however, a fine formation of coral-rag 

 over the oolite. The order of the beds is as follows, beginning 

 with the lowest. 1. Dark-brown shelly beds resembling those 

 associated, at Filey Bridge, Avith the top beds of the calc-grit, 

 and containing the same fossils. 2. Oolitic freestone, many 

 blocks with imbedded fragments of the perna aviculoides. 

 3. Marl beds with numerous casts of the melania striata, sur- 

 mounted by coral rag containing many crystalline stems of 

 madrepores, spines of echinites of the division Cidaris, &c. &c. 

 This order appeared to be identical with that which is exhibited 

 in the Steeple Ashton section. 



In the preceding lists, those species only are enumerated 

 which fell under my own observation, and which may be consi- 

 dered of ordinary occurrence.t The result of the whole exami- 



* Some of the branching stems at Filey Bridge and Scarborough exhibit distinct 

 traces of organic structure. 



+ I have endeavoured, from the only materials in my possession, to convey some 

 notion of the distribution of the organic remains through the several parts of the forma> 

 tion. No one, during a hasty excursion along the coast, has the power of collecting a 

 good suite of fossils. Fine specimens may sometimes be procured from dealers ; but 

 these persons collect from all parts of the coast, and sell the specimens without any cor. 



