IX.—On the Glacial Succession in Europe

^{page 130 note *} Neues Jahrbuch f. Min. Geol. u. Palæont., 1891, ii. pp. 62, 228; Ibid., 1892, i. p. 114.

^{page 131 note *} Naturwissenschaftliche Wochenschrift, Bd. vii. (1892), No. 4, p. 31. The plants were determined by Dr Weber, Professor Wittmack, and Herr Warnstorf. [More recent investigations have considerably increased our knowledge of this flora. See Naturwissenschaftliche Wochenschrift, Bd. vii. (1892), Nr. 24, 25. Ausland, 1892, Nr. 20.]

^{page 132 note *} Beskrifning. till geol. Kartbl. Trolleholm: Sveriges Geologiska Undersökning, Ser. Aa. Nr. 87.

^{page 132 note †} Om de äldre baltiska isströmmen i södra Sverige: Geolog. Förening. a Stockholm Förhandl., Bd. x. p. 157.

^{page 133 note *} Bull, de la Soc. Imper. des Naturalistes de Moskau, No. 4, 1890.

^{page 133 note †} Sederholm, Fennia, i. No. 7; Frosterus, ibid, iii., No. 8; Ramsay, ibid, iv., No. 2.

^{page 135 note *} Geol. Mag., 1881, p. 354.

^{page 137 note *} Morlot, , Bulletin de la Soc. Vaud. d. Sciences nat., 1854, 1858, 1860; Deicke, , Bericht. d. St. Gall, naturf. ges., 1858; Heer, , Urwelt der Schweiz; Muhlberg, , Festschrift d. aarg. naturf. Ges. z. Feier ihrer 500 Sitz., 1869; Rothpletz, , Denkschr. d. schweizer. Ges. f. d. ges. Naturwissensch., Bd. xxviii., 1881; Wettstein, , Geologie v. Zurich u. Umgebung, 1885; Baltzer, , Mitteil. d. naturf. Ges Bern, 1837; Renevier, , Bull, de la Soc. helvèt. d. Sciences nat., 1887.

^{page 137 note †} Penck, , Die Vergletscherung d. deutschen Alpen, 1882; Brückner, , “Die Vergletsclierung des Salzachgebietes,” Geogr. Ahhandl. Wien, Bd. i.; Böhm, , Jahrb. der k. k. geol. Reichsanst, 1884, 1885; see also Fraas, O., Neues Jahrb. f. Min. Geol. u. Palæont, 1880, Bd. i. p. 218; Fugger, E. and Kastner, C., Verhandl. d. k. k. geol. Reichsanst, 1883, p. 136.

^{page 138 note *} Mittheil. des deutsch. u. oesterreich. Alpenvereins, 1890, No. 20 u. 23.

^{page 138 note †} Beiträge z. geolg. Karte der Schweiz, 31 Lief., 1891; Archiv. d. Sciences phys. et nat., 1891, p. 44.

^{page 138 note ‡} “Die grosse Eiszeit,” Himmel u. Erde.

^{page 138 note §} Penck, Die Vergletscherung der deutschen Alpen, p. 228; Verhandl. d. k. k. geol. Reichsanst., 1887, No. 5; Himmel und Erde, 1891. Böhm, Jahrb. d. k. k. geol. Reichsanst, 1884, p. 147. Blaas, , Ferdinandeums Zeitschr., iv. Folge; Bericht. d. nat.-wissensch. Vereins, 1889, p. 97.

^{page 138 note §} Des phénomènes glaciaires dans le Plateau central de la France, &c, Paris, 1869.

^{page 139 note *} Bull. Soc. géol. de France, 1884; see also Boule, M., Bull, de la Soc. philomath, de Paris, 8^e Sér. i. p. 87.

^{page 139 note †} Garrigou, , Bull. Soc. géol de France, 2^e Sér. xxiv. p. 577; Jeanbernat, , Bull, de la Soc. d'Hist. nat. de Toulouse, iv. pp. 114, 138; Piette, , Bull. Soc. géol. de France, 3^e Sér. ii. pp. 503, 507.

^{page 139 note ‡} Mitteilungen d. Vereins f. Erdkunde zu Leipzig, 1883.

^{page 140 note *} For a particular account of the Tay-valley Succession, see Prehistoric Europe, p. 385.

^{page 140 note †} Proc. Roy. Soc. Edin., 1883–84, p. 745; Mem. Geol. Survey, Scotland, Explanation of Sheet 31.

^{page 140 note *} Prehistoric Europe, chaps, xvi., xvii.

^{page 141 note *} British Association Reports (1854): Trans. of Sections, p. 78.

^{page 141 note †} L. Hinxman: Paper read before Edin. Geol. Soc., April 1892.

^{page 141 note ‡} Prehistoric Europe (chaps, xvi. xvii.) gives a fuller statement of the evidence.

^{page 142 note *} Sitzungsberichte d. Kais. Acad. d. Wissensch. in Wien, mathem,-naturw. Classe, Bd. xcvii. Abth. i., 1888.

^{page 143 note *} In some places, however, certain marine deposits (Leda-myalis bed) immediately overlie the Forest-bed. See postea, footnote, p. 145.

^{page 144 note *} Mem. of Geol. Survey, “Pliocene Deposits of Britain.”

^{page 145 note *} The inference that the Forest-bed occupies an interglacial position is strengthened by the evidence of certain marine deposits which immediately overlie it. These (known collectively as the Leda-myalis bed) occur in irregular patches, which, from the character of their organic remains, cannot all be precisely of the same age. In one place, for example, they are abundantly charged with oysters, having valves united, and with these are associated other species of molluscs that still live in British Seas. At another place no oysters occur, but the beds yield two Arctic shells, Leda myalis and Astarte borealis, and some other forms which have no special significance. Professor Otto Torell pointed out to Mr Reid that these separate deposits could not be of the same age, for the oyster is sensitive to cold and does, not inhabit the seas where Leda myalis and Astarte borealis flourish. From a consideration of this and other evidence Mr Reid concludes that it is possible that the deposits indicate a period of considerable length, during which the depth of water varied and the climate changed. Two additional facts may be noted: Leda myalis does not occur in any of the underlying Pliocene beds, while the oyster is not found in the Weybourn and Chillesford Crag, though common lower down in the Pliocene series. These facts seem to me to have a strong bearing on the climatic conditions of the Forest-bed epoch. They show us that the oyster flourished in the North Sea before the period of the Weybourn Crag—that it did not live side by side with the Arctic forms of that period—and that it reappeared in our seas when favourable conditions returned. When the climate again became cold an Arctic fauna (including a new-comer, Leda myalis) once more occupied the North Sea.

^{page 145 note †} Elephas meridionalis is usually regarded as a type-form of the Newer Pliocene, but long ago Dr Fuchs pointed out that in Hungary this species is of quaternary age: Verhandl. d. k. h. geolog. Reichsanstalt, 1879, pp. 49, 270. It matters little whether we relegate to the top of the Pliocene or to the base of the Pleistocene the beds in which this species occurs. That it is met with upon an interglacial horizon is certain; and if we are to make the Pleistocene co-extensive with the glacial and interglacial series, we shall be compelled to include in that system some portion of the Newer Pliocene.

^{page 145 note ‡} Julien, Des Phénomènes glaciavres dans le Plateau central, &c, 1869; Boule, Revue d'Anthropologie, 1879.

^{page 145 note §} Prehistoric Europe, p. 306. Professor Penck writes me that he and the Swiss glacialist, Dr Du Pasquier, have recently examined these deposits, and are able to confirm my conclusion as to their interglacial position.