FLORA OF THE MIOCENE EPOCH. 97 



Gardenia Wetzleri, species of Anona, Nyniphaea Doris, 

 Carpolithes Websteri, C. Boveyanus, and other species. In 

 the post-tertiary white clay of Bovey Tracey, Salix cinerea, 

 and a species allied to S. repens, as well as Betula nana, are 

 found. 



The Arctic fossil flora (Miocene), according to Heer, 

 amounts to 162 species : Crypt ogamia, 18 species, of which 

 9 are large ferns ; Phanerogamia, Coniferte, 31 ; Monocoty- 

 ledons, 14; Dicotyledons, 99. Among the Coniferge are — 

 Pinus M'Clurii, Sequoia Langsdorfiii, Sternbergi, and Coutt- 

 siae, Taxodium dubium, Glyptostrobus europgeus, Thujopsis 

 europgea. Among leafy trees are — Fagus Deucalionis, Quer- 

 cus Olafseni, Platanus aceroides, willows, beeches, Acer, 

 Otopteryx, tulip-tree, walnuts. Magnolia Inglefieldi, Prunus 

 Scottii, Tilia Malmgreni, Corylus INPQuarrii, Alnus Kefer- 

 steinii, Daphnogene Kaimii, probably one of the Laurace^e ; 

 and among Proteaceas, MacClintockia ? and Hakea. In 

 Greenland are found species of Rhamnus, Paliurus, Cornus, 

 Ilex, Crata3gus, Andromeda, ]\Iyrica, Ivy, and Vine. From 

 the flora of Spitzbergen, in the IVIiocene epoch, we may con- 

 clude that under 79° N. lat. the mean temperature of the 

 year may have been 41° Fahr., while at the same epoch that 

 of Switzerland was 69°-8 Fahr. ; judging from the analogy of 

 floras, it appears that the mean temperature has fallen 6° -9. 

 From this it follows that at Spitzbergen, at 78° IS", lat., the 

 mean temperature was perhaps 41°-9 Fahr. In Greenland, 

 at 70°, it would be 49°-l Fahr., and in Iceland and on the 

 Mackenzie, in lat. 65°, it would be 52°-7 Fahr. At the 

 Miocene epoch the temperature seems to have been much more 

 uniform, the mean heat diminishing much more gradually in 

 proportion as the pole was approached. The isothermal 

 line of 32° Fahr. might have fallen upon the pole, while now 

 it is situated under 58° N. (See Heer's conclusions as to 

 changes of temperature depending on proportion of sea and 



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