Freshwater Clays Research Articles

The Pleistocene Avifauna of Arredondo, Florida

An extensive fauna of Pleistocene vertebrates occurs at Arredondo, Florida. The bone bed lies in a fresh water clay which is here named the Arredondo clay member of the Wicomico formation. The geographic extent of this member includes 10 localities in 3 counties of northern Florida. The sediments were deposited below the present 100-foot contour under cooler climatic conditions during the Illinoian glacial stage. The environment included a fresh water marsh community with nearby scrub. The avifauna of 43 species includes forms still living, interglacial relicts, and glacial indicators. Five living species of birds are added to the fossil record, and six others to the Pleistocene fauna of Florida. Four species are described as new: Falco readei, Colinus suilium, Dorypaltus prosphatus (n. gen., Charadriidae), and Cremaster tytthus (n, gen., Icteridae). The name Podilymbus magnus Shufeldt is revived. Limicolavis pluvianella Shufelat, from the Oligocene of Oregon, is removed from the Charadriidae; it must be left in incertae sedis until the type is restudied.

On a Deposit of Interglacial Lœss, and some Transported Preglacial Freshwater Clays on the Durham Coast

I. Introduction. The object of this paper is to describe some phenomena connected with the earlier Glacial deposits that are exposed on the Durham coast. The beds to which attention is more particularly directed form part of, or are connected with, a recently-discovered deposit of Scandinavian Drift. They comprise the following:— (1) A bed of material that, in chemical, physical, and stratigraphical characters, presents every appearance of complete identity with the true loess of the European Continent. (2) Some deposits of brown, grey, and bluish clay containing a varied assortment of organic remains, including shells of non-marine mollusca, ostracod valves, mammalian bones and teeth, trees, seeds, mosses, and other plant-remains: the whole having been transported by the advancing Scandinavian ice-sheet. Both the above-mentioned deposits, in common with other phenomena connected with the earliest advance of the Scandinavian ice-sheet, are preserved in Preglacial hollows, valleys, and fissures in the Magnesian Limestone. All of them are earlier than, and completely underlie the later local Glacial accumulations, to which I gave the appellation of Main Drift, and containing local English and Scottish erratics. These erratics are completely wanting in the underlying earlier deposits with which this paper deals. A few words in recapitulation of matter already published are necessary, in explanation of the peculiar features and mode of occurrence of the bed of Scandinavian Drift which is exposed on the Durham coast. Up to the year 1914, when I investigated and described this bed

Societies and Academies

LONDON. Geological Society, December 18, 1918.—Mr. G. W. Lamplugh, president, in the chair.—C. T. Trechmann: A bed of inter-Glacial loess and some pre-Glacial freshwater clays on the Durham coast. A few years ago the author described a bed of Scandinavian drift that was found filling up a small pre-Glacial valley-like depression at Warren House Gill, on the Durham coast. This section, and others north and south of it, have been kept under observation at different times, and several new features have been noticed as the high tides and other agencies exposed parts of the coast. All the observed features seem to point to the fact that the Scandinavian ice-sheet advanced on the east coast of England in the same way as it invaded northern Europe round the southern shores of the Baltic, and gave rise to analogous climatic conditions leading to the formation of loess, a fragment of which is found protected from the erosive action of the later local glaciation in a small hollow on the Durham coast.

On the Occurrence of the Remains of a Cetacean in the Lower Oligocene Strata of the Hampshire Basin

Remains of the marine mammalia have been so seldom recorded from the Lower Tertiaries of Britain, that the discovery of a new form is of considerable interest to the geologist. Up to the present time the only species noticed was the Zeuglodon Wanklyni , described by Prof. Seeley in 1876. The remains of this species, which were found in the Barton Clay, would appear to have been unfortunately lost. The form which I have now the honour of laying before the Society is represented by a caudal vertebra only; but this appears to present some very interesting peculiarities. The locality from which this specimen was obtained is Roydon, about a mile and a half south of Brockenhurst, in the New Forest. The brickyard at this place is almost the only locality in the New Forest at which the very interesting marine fauna of the Brockenhurst Series can now be collected. The beds exposed at this brickyard consist of sandy clays crowded with marine fossils; they have been exposed to the depth of 25 feet; but as no overlying freshwater beds have been seen in conjunction with them, the total thickness of the Brockenhurst Series cannot be determined. Judging, however, from the wide area over which the beds of this age have been found to be exposed, that thickness must be considerable. These thick marine strata are seen at Roydon to rest directly upon freshwater clays of a bright green colour and crowded with specimens of Unio Solandri , Sow., which doubtless belong.