276 



PROCEEDINGS OE THE GEOLOGICAL SOCIETY. 



[Feb. 5, 



At the eastern end of the Tunnel, the Lincolnshire Limestone 

 appears in massive beds of hard, compact, marly, blue-hearted lime- 

 stone. The crown of the Tunnel arch reaches up into the lower 

 beds of tbe Upper Estuarine Clays, which here, as elsewhere, are 

 characterized by the basal ferruginous band. Many tons of this 

 band (which assumes an almost septarian character in places) were, 

 some years ago, experimentally smelted by the late Marquis of 

 Huntley, and a good quality of pig-iron was produced. 



The Great Oolite Limestone surmounts the Upper Estuarine Clays, 

 and forms the surface-rock over the Tunnel ; at a short distance 

 south, it is overlain by the Great Oolite Clay ; and this, in turn, in 

 less than half a mile in the same direction, by the Cornbrash. 



Thus (as I have shown) upon a line between Stamford Field, on 

 the north, and a point half a mile south of the "Wansford Tunnel, a 

 distance of about 8 miles, the Lincolnshire Limestone is the pro- 

 minent surface rock ; and at each end of this line, is an escarpment, 

 presenting a perfect sequence of beds from the Cornbrash to the 

 Upper Lias inclusive, in which the distinct individuality of the 

 beds of the Great Oolite Limestone and of the Lincolnshire Lime- 

 stone is unmistakably demonstrated, and the true place of the latter 

 formation in that sequence as certainly determined. 



East of the "Wansford Tunnel, on the Huntingdonshire side, and 

 at Castor on the Northamptonshire side, of the river Nene, are 

 quarries in the Lincolnshire Limestone ; and from these, I have 

 numerous fossils : those from Castor include Goniomya literata, 

 Sow. sp., &c. 



Fossils from the Lincolnshire Limestone, South of the Nene, near 

 Wansford, Hunts. 



Shelly and Freestone Beds. 



Astarte depressa, Mor. fy Lye. 



elegans, Sow. 



excavata, Sow., var. compres- 



siuscula, Mor. $' Lye. 



minima, Phil. 



recondita, Phil. 



rhomboidalis, Phil. sp. (young). 



, sp. ? 



Cucullaaa oblonga, Sow. 



Homomya crassiuscula, Mor. §~ Lye. 



(young). 

 Lucina Bellona, aV Orb. 



despecta, Phil. 



Wrightii, Oppel. 



Macrodon Hirsonensis, d'Arch. sp. 

 Modiola gibbosa, Sow. 

 Myoconcba crassa, Sow. 

 Mytilus lunularis, Lycett. 

 Opis lunulatus. Sow. sp. 



similis, Besh. (or new sp. ?). 



, smootb new sp. ? 



Pboladomya fidicula, Sow. 

 , large new sp. ? 



Hinnites abjectus, Phil. 



velatus, Goldf. sp. 



Lima bellula, Mor. $ Lye. 



punctata, Sow. 



Ostrea flabelloides, Lam. (young). 



— gregaria, Sow. 



, sp. ? (young), mimetically 



marked. 



, sp? 



Pecten articulatus, Schloth. 



demissus, Phil. 



, small smooth sp. ? 



, new sp.? 



Perna rugosa, Goldf. (young). 

 Pteroperna costatula, Deslong. 



(young). 



plana, Mor. fy Lye. (young). 



Tricbites nodosus, Lycett. 



Area £emula, Phil. 



Prattii, Mor. $• Lye. 



pulcbra, Sow, 



, sp. (likeXilTerti^/o*-, ^Lyc.)? 



, sp. ? 



sp. 



