Page:Quarterly Journal of the Geological Society of London, vol. 29.djvu/119

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1872.] MEYER PUNFIELD SECTION. 75


covery. Its position should be somewhere between the hard bands G and E of my section.

The letters C and B on diagram fig. 1 indicate respectively the "marine band" and the "laminated clays and sands with lignite" of the Punfield strata. Of these I have nothing new to say.

The diagram fig. 2 illustrates in full my present reading of the Punfield section. It shows at a glance the comparative thickness and succession of the various groups of strata between the Gault and the Middle Wealden, and their (probable) respective relation to the Wealden and Neocomian (Lower Greensand) of the Isle of Wight.

The points involved in this question, "as to the relation of the Punfield strata to the Wealden and Neocomian," are at the present moment necessarily of considerable interest; but, while feeling that I am but doing my duty as a student of Secondary geology, in once more bringing this subject before the Geological Society, I must disclaim any desire that the question should remain to be decided on my evidence alone.

Discussion.

Mr. Judd congratulated the author on the interesting nature of his discoveries, which in his opinion bore out most completely his own views and those of others who had worked before him in the same field. He cited Dr. Fitton, Mr. Godwin-Austen, and Sir Charles Lyell as regarding the beds as unquestionably Wealden, though with some marine bands accidentally intermingled. Prof. Ed. Forbes, Prof. Phillips, and the Geological Survey had also regarded these beds as Wealden, notwithstanding the temptation there existed from stratigraphical reasons to place them in the Lower Greensand. These authors had supported their views of the Wealden nature of these beds by collections of freshwater fossils, some of which were figured, and are still preserved in public collections. He had himself regarded the Punfield series as Neocomian, though still closely connected with the Wealden, and, in fact, forming a transitional series of beds between the two, though absolutely belonging to neither, and therefore worthy of a distinctive name, in this respect resembling the Purbeck and Rhaetic. He accepted the author's view, as carrying the boundary of these transitional beds to a lower level than that previously assigned to them. In correlating the Punfield beds with those of the Isle of Wight, he disputed the value of the evidence of the lobster-beds, which, as had been pointed out by Edward Forbes, must of necessity have varied in character at points any considerable distance apart.

Mr. Seeley had regarded the Punfield beds from the same point of view as Mr. Meyer, and had all along felt objections to the opinion of Mr. Judd. This had been partly the result of his observations of the section, partly the result of the paleontological evidence. By following the beds westward he had arrived nearer the source of the materials of which they were composed, and had noted more particularly a certain grit-bed which he thought could be recognized through the whole series, and therefore afforded a sort