January 21, 1892^ 



NATURE 



275 



it in some other places on the coast of Norfolk. Besides 

 Salix polaris, Mr. Reid has also found in it leaves of 

 Betula nana and seeds of some other plants. At Hoxne, 

 in Suffolk (18), Messrs. Reid and Ridley have discovered 

 Salix polaris, S. myrsinites, and Belula nana, together 

 with many other species in a glacial fresh-water deposit 

 of a precisely similar character to those in Southern 

 Sweden. Again, in 1879, I found leaves of Betula nana 

 in a peat-moss at Bridlington (21), and the same plant 

 has been found by Mr. Reid at Holmpton (20). Accord- 

 ing to a statement of Mr. Reid, Salix herbacea was found 

 some years ago by Mr. Bennie in an inter-glacial deposit 

 at Hailes, about three miles from Edinburgh. Finally, 

 during this present year (1891), Mr. Reid has himself 

 discovered a rich Arctic flora, yielding Salix polaris, 

 S. herbacea, S. reticulata. Azalea procutnbens , and Betula 

 nana, in lacustrinedepositsimmediately above the boulder- 

 clay near Edinburgh (22). ^ 



Returning to Sweden, a great many new localities yield- 

 ing Arctic plants have also been found in Scania since 

 1 87 1, partly by myself, partly by Dr. Gunnar Andersson 

 and others, so that the number of localities in Scania (i) 

 now exceeds thirty. In Ostrogothia; leaves of Betula 

 nana and Dryas octopetala, &c., were found in 1886 in a 

 calcareous tufa near Vadstenaat Lake Vetter (2) ; and in 

 the isle of Gotland (3), Mr. R. Sernander, in 1890, dis- 

 covered leaves of the same species in a fresh-water deposit 

 overlain by the curious gravel-bed containing Ancylus. 

 In Jemtland, Mr. A. F. Carlson, in 1885 and 1886, dis- 

 covered leaves of Dryas and Salix reticulata in calcareous 

 tufa in several localities (4) far removed from the regions 

 where these species now exist. In Norway nothing what- 

 ever was known of the ancient Arctic flora until last summer 

 (1 891), when, according to Prof. A. Blytt, leaves of Dryas 

 octopetala were found in calcareous tufa at Leine (5). 

 In Denmark the continued researches of Prof. Steen- 

 strup have added many new localities (6) to the original 

 ones mentioned above, not only in Seeland, but also 

 (from a private communication made to the author) on 

 the isle of Moen (6'), in Northern Jutland (6"), and on 

 Bornholm (6'"). Turning to Switzerland, Prof C. Schroter, 

 of Zurich, has discovered three new localities for the 

 glacial flora, and in 1880 I myself found leaves of Salix 

 herbacea, Dryas octopetala, and Betula nana in a fresh- 

 water deposit near Hedingen (Canton Zurich), and leaves 

 of the last-mentioned species underneath a peat-moss at 

 Wauwyl (Canton Luzern), and in peat at Le Chaux de 

 Fonds. 



It ought also to be mentioned that Prof. M. Staub, 

 of Buda-Pest, has lately described a fossil glacial flora' 

 from the Southern Carpathians, which, besides seeds of 

 Pinus Putnilio and Pi?ius Cenibra, also contains leaves of 

 Dryas octopetala, Betula nana, and Salix inyrtilloides, 

 together with fruits of Tofieldia borealis, thus proving the' 

 existence of a somewhat colder climate than the present 

 one. 



In 1880, I discovered a locality at Neetzka, in Mecklen- 

 burg, not far distant from Oertzenhof where I had found 

 Betula 7iana in 1872. The new locality (14) yielded 

 Dryas octopetala, Salix reticulata, Betula nana, B. 

 odorata, and B. verrucosa, together with leaves of 

 Myriophyllum, some other Salices and mosses, such as 

 Hypnum scorpioides and H.Jiuitans. According to the 

 manner in which the samples of clay were gathered, it 

 is very possible that the species mentioned belong to 

 different horizons. 



Neetzka and Oertzenhof being the sole localities in 



I It is curious that Dryas octopetala has not yet been reportid from the 

 glacial plant-fossils of Great Bnt»in, althouRfi it abounds in the glacial 

 fresh water deposits of Sweden, Denmark, Germany, and Russia ; and 

 although the plant still lives in the mountains of Scotland, Yorkshire, and 

 Wales. May not, however, the leaf from Crofthead which Mr Mahony 

 has identified with. SV«/^//ar/(rjfa/<rr/f»//a/a(C>c)/. Mag., vol. vi. p. 392) in 

 reality ha ^e been a leaf of Dryas > The leaves of Scutellaria can hardly be 

 preserved in the fossil state. 



NO. I 1 60, VOL. 45] 



Northern Germany which until then had yielded fossil 

 Arctic plants, while nothing whatever was known of the 

 existence of Arctic plant-fossils in Russia, Prof. O. Drude, 

 of Dresden, in 1 889 expressed the opinion ^ that the margin 

 of the great northern inland ice might have been sur- 

 rounded, not by an Arctic flora, but by a forest growth ; 

 and further, that such a growth may even have existed on 

 the surface moraines of the inland ice itself. 



I have- lately tried to show, however, that this hypothesis 

 is erroneous; but with the conviction that facts would prove 

 the best arguments, I resolved to visit those portions of 

 Western Russia and Northern Germany which I had not 

 previously examined, and, thanks to the liberality of the 

 Swedish Society for Geography and Anthropology, who 

 gave me the balance of the Vega fund, I have been enabled 

 to carry out my project, with the results communicated 

 below. As my collections are, however, only partially 

 worked out as yet, the present notice must be considered 

 as only preliminary. 



The circumstances under which the Arctic plant- 

 fossils occur are pretty uniform, and it may therefore be 

 convenient to state them at once, instead of giving a 

 description for every locality. In those parts of \Vestern 

 Russia and Northern Germany which I visited, the 

 ground almost everywhere consists of a true moraine 

 profonde (till) which has never been covered by the sea. 

 Though marine glacial deposits are consequently absent 

 in this area, fresh-water deposits, which have been formed 

 in ancient lakes or ponds, are very abundant. These 

 deposits consist generally in their lower part of a bluish 

 clay or sandy clay, sometimes distinctly laminated, while 

 the colour of the clay in the upper part is generally some- 

 what yellowish. This fresh-water clay is often covered by 

 white shell marl, principally derived from the shells of 

 fresh-water MoUusca ; sometimes, however, by mud con- 

 taining the remains of microscopical Algas, fragments and 

 excrements of insects and other minute fresh-water 

 animals. Then comes the peat, terminating the deposit 

 above— sometimes developed as a true peat-moss ; at 

 others, only as a peaty mould i to 2 feet thick. In 

 places the peat is totally absent, i.e. the fresh- water lake 

 has been entirely filled up by the alluvial clay before the 

 formation of peat had begun. 



The Arctic plant-fossils are found principally in the 

 clay, sometimes also in the white marl or mud, whilst 

 only Betula nana ascends into the peat. Some fresh- 

 water Mollusca are found together with the Arctic plants 

 — namely, some species of Pisidiwn, Litnncea ovata, 

 Anodonta or Unio, sometimes also Cyclas cornea. By 

 studying the distribution of the Mollusca in the different 

 horizons, the order of immigration of the different species 

 can be ascertained, and we know now very well the manner 

 in which this has taken place in Southern Sweden. Besides 

 Mollusca, the Arctic plants are often accompanied by re- 

 mains of beetles and by Ustracoda, such as Cytheridea 

 torosa and others ; and in one locality in Scania I have 

 also found abundant remains of Apus glacialis. Finally, 

 it is in this horizon that the remains of the reindeer are 

 principally found in Southern Sweden, Denmark, and 

 Northern Germany. 



When travelling in Esthonia and Livonia I had the 

 advantage of being accompanied by the well-known 

 geologist, Akademiker Fr. Schmidt, of St. Petersburg, 

 and the success of our investigations was largely due to 

 his advice. The Arctic plant-fossils were first discovered 

 at Kunda in Esthonia (7), where the fresh-water marl 

 and clay are used in the preparation of cement. The 

 upper part of this deposit has yielded a great many bone 

 implements of Neolithic age, which were described 

 some years ago by the late Prof Grewingk, of Dorpat, 

 and antlers of reindeer are likewise present. The Arctic 

 plants were obtained at a depth of 17^ feet below the 



t Peiermann's Mitteiluftgen, 1889, pp. 282-290. 



" EngUt's Botan. Jahrbiicher, Bd. xiii., 1891, Beiblatt Nr. zj. 



