Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/685

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survivors from the yet earlier Diestien epoch, viz. Voluta, Cassidaria, Pyrula, Chama, and others. In its later period, conditions had so far changed that none of these forms were remaining in the Eed-Crag sea ; and as it turned over the previous accumulations of shell-masses it added little thereto but boreal forms ; and it was at this period and in this condition of things that the Norwich-Crag area became also the recipient of a shelly deposit, and remained apparently subject to such conditions (if we may judge by the increase of northern forms of mollusca in its higher parts) until a later period than we have evidence of in Suffolk, and when the arctic tendency of the fauna had become still more pronounced.

The Scaldisien beds, or Yellow Crag of Antwerp, do not bear evidence of quite so late a date as that of the newer element of the Red Crag of Suffolk and its equivalent in Norfolk. It appears to be entirely homotaxial with the earlier element of the Red Crag and the Coralline Crag. A closer examination of the Scaldisien fauna would be valuable at the present time.

The occurrence of large and remarkably perfect specimens of Voluta Lamberti, Cassidaria bicatenata, and Atractodon elegans on the beach at Felixstow in former years, together with hundreds of specimens of Turritella imbricataria, has never been satisfactorily accounted for. The destruction of Crag beds on the coast does not appear to be sufficient to have furnished so many specimens, although it is to be remembered that the whole of the Red Crag once existing at Harwich has disappeared beneath the sea. It does not seem improbable that these remarkable beach-specimens are the remnants of the Crag deposit which extended once towards the present Belgian coast, and which long since imbedded among other debris in the accumulations of the German Ocean, have now, by some change of current, been thrown up on the shore line.

The question as to what may be the relation of the Suffolk bone- bed and its contents to the Norfolk stone-bed and its contents is one of considerable interest and difficulty. They have this in common, that they contain the detached molars of Mastodon arvernensis ; but the Norfolk bed also contains teeth of Elephas meridionalis, whilst no Elephant has ever been found in the Suffolk bone-bed*. The Suffolk bed contains phosphatized lumps of Eocene clay, with included mammalian, reptilian, piscine, molluscan, and crustacean remains of that age, also nodules of sandstone (called " box-stones ") containing Diestien Mollusca, Sharks, and Cetacea, the bones and teeth of which also occur in a rolled and polished state ; thirdly, teeth of Rhinoceros Schleiermacheri, of Tapirus prisms, of a peculiar Hyoena, of Hipparion, of a Trilophodont Mastodon, and of other terrestrial Mammals. None of these things have been found in the Norfolk bed ;

  • After the reading of this paper, Mr. Gunn exhibited a fragment of an

Elephas molar found in a Red-Crag pit. I have a very fine specimen of the kind, and others have been recorded and deceived the late Dr. Falconer. It is easy at once to decide from their mineral condition that these specimens do not come from the Suffolk bone-bed at all, but from the large mass of overlying sandy strata.