Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/361

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from the deposits in Eastern Spain we have thirty- nine or forty in Britain. The fauna was, indeed, precisely the same. He referred to several of the species, and intimated his intention of describing and figuring 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 all the sections, and was convinced that they showed neither a physical nor a palaeontological break, and that the several beds could be so well traced that the base of the section at Swanage was superior to that seen in the section at Brixton, in the Isle of Wight. He identified the shell noticed as a Vicarya as a Greensand form. There was nothing in the fossils to indicate a separation from the Lower Greensand, of which he regarded these beds palaeontologically 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 Vicarya 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 Rev. O. 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 disappearance of a great mass of Lower Greensand.

Mr. Judd, in reply, said that 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 confusion, as might be seen by the stratigraphical attempts of the predecessors of William Smith. The name Vicarya for the shell which had been referred to was only provisionally adopted, on the authority of De Verneuil and other writers.