CARBONIFEROUS OOLITE OF BRORA. 



519 



identical with those of the middle and inferior oolite 

 of the eastern moorlands, and north-eastern coast of York- 

 shire ; and as in that district, the lower beds of the Coral- 

 rag pass into a yellowish .sandstone, beneath which is 

 shale containing belemnites, and from under this bed the 

 carboniferous strata emerge. This series of deposits rests 

 on Lias shale.* Many of the fossils are identical with 

 those of the pier-stone of Scarborough, which there over- 

 lies the main coal-seams. 



The fossil plants are for the most part of the same type 

 as those of Yorkshire, and are associated with shells of 

 the genera Cyclas, Unto, Paludina, and species of Tettina, 

 Perna, &c. : cases of the Cypris granulosa (p. 405) also 

 occur in profusion. Scales and teeth of numerous small 

 ganoid fishes, of genera common in the Oolite, (Hybodus, 

 Lepidotus, Acrodus,) abound in some of the layers of 

 clay: fragments of plates of Turtles are, I believe, the 

 only reptilian relics hitherto observed. 



These carboniferous deposits have evidently had the same 

 origin as those on the Yorkshire coast, in which Uniones 

 and Cyprides are associated with Ferns, Zaniias, Thuyites, 

 and other terrestrial plants. t Taken as a whole, the fluvio- 

 marine intercalations of the oolite must be regarded as 

 local accumulations of the spoils of the land, transported 

 into the bed of the ocean by the agency of rivers and 

 currents ; the presence of coal depending on the streams 



* The interesting Memoir of Sir R. Murchison on the Coal-field of 

 Brora should be referred to for details. Geol. Trans, vol. ii.; also, a 

 valuable paper by Mr. Robertson on the same, Geological Journal, 

 vol. Hi. p. 113. 



f Mr. Bakewell has described a coal-mine, in which seams of coal 

 are intercalated with calcareous strata, in a mountain-range near the 

 Lake of Annecy in Savoy ; and which, from the shells in the lime- 

 stones, he considered as belonging to the same period as the carboni- 

 ferous oolite of Yorkshire. See Travels in the Tarentaise, vol. i. 

 p. 185. 



