10 Mr. N. J. Winch on the Geology of 



In length it is about 8§ inches, and 4| in breadth. The dorsal fin 

 reaches from the middle of the back to the tail. 



From Humbleton quarry, situated a mile from Bishop Wearmouth, 

 on the road to Durham, I have received the following specimens, 

 imbedded in hard buff-coloured crystalline limestone. 



1. Casts of the internal part of the vertebral column of the Cap 

 Encrinite. See Parkinson, vol. 2. tab. 10. fig. 4. 



2. A species of Donax with hair-like spines. 



o. Casts of reticulated Alcyonite. Parkinson, vol. 2. tab. 1 0. 

 fig. 1, 2, 3. 



4. Smooth shelled bivalves, from the size of a pea to that of a 

 cockle, resembling those of the genus Donax. 



5. Small round bodies, delineated by Parkinson, vol. 2. tab. 8. 

 fig. 10. 



6. Casts of bivalves, resembling muscles. 



7. Casts of Arc3e and Anomise. Sowerby, Brit. Min. tab. 55, 



8. Impressions of a reticulated marine production resembling 

 the genus Flustra. 



III. Coal Measures, 



The coal-seams and the rocky strata which together constitute the 

 coal-formation of Newcastle and Sunderland, are in part covered by 

 the magnesian limestone, and rest upon the lead-mine measures. 

 They occupy a hollow, or trough, of which the extreme length from 

 the Aklington colliery, near the Coquet, in the north, to Cockfield, 

 in the neighbourhood of West- Auckland, is 58 miles; and the 

 breadth, from By will on the Tyne, to the sea-shore, is 24 miles. 

 This formation first makes its appearance on the south bank of the 



