Professor E. Forbes on the Oolite in Skye. 97 



9. Ferruginous sands with fragments of wood, pyritised 

 and in the state of jet, one foot. 



10. Concretionary limestone with Belemnites, one foot. 



11. Soft white sands with traces of bivalve shells, appar- 

 ently Cyrenm, three feet. 



12. Hard sandstones with Perna and numerous Ostrece 

 and CyrencB^ two feet. 



13. Greyish sands with carbonaceous streaks and lenticular 

 courses of comminuted shells ; concretions in places ; five feet. 



14. Hard calcareous shales with bands of Cyrence and 

 fossil wood, three feet. 



15. About fourteen bands of loose calcareous slaty and 

 shaly beds filled with Cyrence, occasional Uniones, and Ostrece : 

 these appear to constitute a thickness of about twelve feet, 

 but the base of them resting on tjie basalt is concealed under 

 water. 



The dykes of trap in communication with the superincum- 

 bent amygdaloid bake the strata through which they pass 

 and alter the mineral character of the fossils. 



The position of these estuary beds, beneath the Oxford 

 clay and above the mass of the middle oolites, at once 

 removes them from identification with Wealden or tertiary 

 strata of the South of England, and as readily suggests a 

 comparison of them with the so-called " Wealden beds," dis- 

 covered by Mr Alexander Robertson, intercalated with the 

 carboniferous portion of the oolitic strata of Brora in Suther- 

 landshire, and described by that gentleman in two most 

 interesting papers communicated to the Geological Society 

 in 1843 and 1846. The main seam of Brora coal lies imme- 

 diately beneath a stratum containing Kelloways Rock fossils, 

 and regarded by Sir Roderick Murchison as the representa- 

 tive of the pier stone of Scarborough. Below the coal beds 

 are bituminous shales, clays, and a thin layer of whitish 

 argillaceous limestone, containing numerous remains of Fish, 

 and of shells of the genera Cyclas or Cyrena^ Unio, Perna, 

 Tellina, and Paludina, These shales are superior to the 

 oolitic and liassic strata. 



Mr Robertson enumerates the many fossils found by him, 

 but does not describe or figure the new species. Of the fresh- 



yoL. LI. NO. CI. — July 1851. g 



