THE FIRST FORESTS OF MODERN TYPE. 199 



that the lignite of this locality represents an ancient peat-moss, 

 which must have been of wide extent, with reeds, sedges, 

 birches, poplar, and certain conifers growing on its banks ; 

 while the higher and drier ground in the neighbourhood 

 probably supported a growth of pines and firs, with elms and 

 hazel-bushes. The remains of water-lilies suggest the existence 

 of a fresh-water lake in the old peat-moss, which must have 

 remained unfrozen during a great part of the year." 



It is to be observed, with reference to the Miocene age of 

 these beds, that as the Miocene flora of Europe and America 

 migrated from the north, the plants found in the beds of that 

 age in the temperate latitudes may really be Eocene in the 

 Arctic regions, a fact which produces some uncertainty as to 

 their actual age ; and even in temperate America there is 

 reason to believe that a flora which in Europe might be called 

 Miocene existed in Eocene times, and extended with com- 

 paratively little change thiough the Miocene into the Pliocene 

 period. 



The warmth required for the growth of luxuriant forests 

 near vhe Pole might be secured by a different distribution of 

 land and water, and of the oceanic currents, but the require- 

 ments of plants as to light seem more difficult to meet, and it 

 has been doubted whether species similar to those which 

 are accustomed in modern times to regular alternations of day 

 and night could submit to the long Arctic winter darkness. 

 It is known, however, that in conservatories in Northern Russia 

 plants supplLJ with heat and moisture can endure in winter 

 great deprivation of light, and at Disco, in Greenland, roses 

 and fuchsias flourish as house plants.^ These facts show that 

 if there were sufficient light and heat in summer, . great 

 number of tlic plants of temperate latitudes could endure 

 extreme cold and much deprivation of light in winter. 



It may be well here to inform the render that some confusion 

 as to the succession of the Cretaceous and Tertiary floras in 



^ Lyell, Principles ; Brown, Florula Diicoana, 



