140 Reports and Proceedings. 



describing and figm-ing those forms which have not been detected in the Spanish 

 deposits. 



Mr. Seeley stated that he could not agree with Mr. -Judd in his conclusions, and 

 that he objected to the method adopted by him. He had examined aU the sections, 

 and was convinced that the strata at Swana^e were all superior to those seen in the 

 section in the Isle of Wight. He regarded the shell noticed as a Viearya, as a 

 Greensand form. There was nothing in the fossils to indicate a separation from the 

 Lower Greensand, of which he regarded these beds as forming a part. Each division 

 was to be traced westwards continuously, but changing in mineral character. Mr. 

 Seeley objected to the correlation of these deposits with others occurring in Spain or 

 any other distant locality, and considered the community of fossils not sufficient to 

 establish such a correlation. He objected also to the introduction of a new term into 

 geological nomenclature. 



Mr. Jenkins remarked on the value of Mr. Judd's description of the sections, even 

 if his deductions were to be rejected. He regarded the establishment of a Punfield 

 formation as unnecessary, and cited the Purbeck and Portland beds as examples of 

 analogous freshwater and marine deposits. He indicated that the Weald may be 

 regarded as the freshwater equivalent of the Lower Neocomian. He doubted 

 whether the shell referred to Viearya really belonged to that genus. Ammonites 

 Deshayesii was said to have a restricted range in time. Mr. Jenkins remarked 

 that it was very widely diffused, and therefore should have a wide range in time, 

 which would invalidate the argument founded on it. 



The Eev. 0. Fisher stated that in 1853 he had observed a fault cutting off the 

 Gault from the Punfield Beds, and that its position might account for the disap- 

 pearance of a great mass of Lower Greensand. 



Mr. Judd, in reply, said he did not propose the term " Punfield Formation " as a 

 definitive term, but only as a matter of convenience. He believed that strata could be 

 positively identified by the organic remains contained in them, although the method 

 may have been grossly abused. Physical investigations alone led to nothing but con- 

 fusion, as might be seen by the stratigraphical attempts of the predecessors of William 

 Smith. The name Viearya for the shell which had been referred to wa§ only pro- 

 visionally adopted, on the authority of De Verneuil and other writers. 



2. " Some remarks on the Denudation of the Oolites of the Bath 

 district, with a theory on the Denudation of Oolites generally." By 

 W. Stephen Mitchell, Esq., M.A., F.G.S., of Gonville and Caius 

 College, Cambridge. 



The author briefly referred to the theory according to which 

 Oolitic deposits were supposed to have been originally spread out in 

 continuous sheets over the country which they occupy, and to owe 

 their division into separate hills to the action of denudation after 

 their original deposition and consolidation. He suggested, as an 

 equally probable hypothesis, that whilst the marls and clays of 

 Oolitic areas were probably originally deposited in continuous beds, 

 the limestones in many cases may never have extended beyond 

 the areas now occupied by them. He described the beds of lime- 

 stone in the Oolitic hills as thinning out towards the valleys on all 

 sides, maintained that the limestones owed their origin to coral reefs, 

 and cited several descriptions of coral islands by the late Prof. Jukes, 

 to show the agreement in their structure with that which he ascribed 

 to the Oolitic hills. He assumed that in the event of a coral-area 

 becoming one of sedimentary deposition, the sedimentary deposit 

 would' preserve intact the contour of the coral islands, and inferred 

 that this has been the case in the Bath district, so that the Great 

 Oolite cappings of the hills of that area may represent the original 

 contours of coral islands, exposed by the denudation of the Bradford 

 clay. The amount of denudation undergone by the Great Oolite 



