318 Mr. MuRCHisoN on the Coal-jield of Brora in Sutherlandshire, 



predict with certainty, that no carboniferous deposits of any great value will 

 ever be discovered, at all events in Great Britain. A want of such knowledge 

 has induced many persons to make trials for coal in beds subordinate to the 

 English oolites, and even superior to them, in places where the type of for- 

 mation did not otfer the least warrant for such attempts. These speculations 

 have ended, and always must end, in disappointment and ruin. 



TABLE OF FOSSIL SHELLS. 



The Figures refer to " Mineral Conchology," and the new species have been named by 



Mr. Sowerby. 



List of Species and their Localities in 



SCOTLAND. 



Braambiiry Hill quarries or highest beds in the 

 Brora district, consisting of rubbly limestone 

 and siliceous sandstone. 



Chambered Univalves. 

 Ammonites vertebralis. Tab. 163 , . . . 



— cordatus. Tab. 17, fig. 2 and 4 



— perarmatus. Tab. 352 . . . 



— new species, not figured, resembling 



a nautilus. 



— new species, with bifid ribs. 



Bivalves. 

 Cardium dissimile. Tab. 553, fig. 2 . 



Cucullaea, 2 species, not determined 

 Gryphxa nana. Tab. 383, fig. 3 . 



bullata. Tab. 368 



Lucina crassa, new species. Tab. 557, fig. 3 



Modiola bipartita. Tab. 210, fig. 3 and 4 . 

 Pecten, large ribbed species, not vet figured 



Formations and Localities in which the same 

 Species occur in 



ENGLAND. 



Calcareous grit and sandstone, or base of the 

 coral rag formation. 



In a siliceous limestone of the calcareous grit 

 beneath the coral rag at Dry Sandford and 

 Marcham, Oxon. — Base of the calc. grit, 

 Sevenbeck, Eastern Moorlands of Yorkshire. 



In the calc. grit of Shotover Hill, Oxon ; Cay- 

 ton Bay and Scarborough Cliff, Yorkshire. 



Abingdon, Oxon. ; Malton and Scarborough 

 Cliff, Yorkshire. 



Portland, Tisbury, Aylesbury, &c.— It is re- 

 markable that this fossil, hitherto called the 

 Venus ofthe Portland-stone, is found at Brora 

 in a mass of fossils of the calcareous grit. 



The genus cuculljea is found in almost every for. 

 mation above the lias. 



In groups in the calcareous grit, Scarborough ; 

 also at Shotover Hill, Oxon. 



Horncastle, Lincolnshire; also at Scarborough? 



Horncastle,Lincolnshire; Fcldmarsham,Oxon ; 

 Scarborough Cliff? 



Bedford Castle ; Scarborough Cliff, &c. 



Marcham Field, Oxon ; and Scarborough Cliff. 



