i8o NATURAL SCIENCE. March. 



species of Salisburia, similar to those described by Heer from the 

 Jurassic of Siberia. The lower beds of this (the Kootanie series) are 

 not known to contain any angiosperms, but in beds a little higher 

 (Intermediate and Mill Creek beds) these begin to occur. Newberry 

 has found the same flora farther south in Montana, and it corre- 

 sponds, in part at least, with the Potomac flora of Fontaine, which 

 occurs over a wide area in the South-Eastern States of the American^ 

 Union. The geographical distribution of this flora shows an exten- 

 sion of warm climate up to the territory of Alaska. With other 

 geological facts, it also shows that the habitat of the Lower Cre- 

 taceous flora was around the margin of a continent not yet elevated 

 into lofty mountain chains, and including to the south a mediterranean 

 sea of warm water ; while the conditions in the extreme north must 

 have excluded anything representing the present snow-clad mass of 

 Greenland. This alone is, in my judgment, sufficient to account for 

 the climate of the period, whose warmth extended even to Greenland. 

 I have noticed the nature and correlation of this flora in papers 

 published in the Transactions of the Royal Society of Canada (1S85, 

 part iv., p. I, and 1892, part iv., p. 79). 



This is succeeded in the north of Canada, at least as fai; to the 

 south as the latitude of 55°, by the Dunvegan series, holding a warm, 

 temperate flora, containing species of Magnolia, Laurus, Ficus, and 

 Quercns, along with such temperate forms as Fagiis and Betula. It 

 also contains Cycads and Sequoias {Trans. Roy. Soc. Canada, 1882, 

 part iv., p. 20). It appears to be in the main parallel with the 

 marine Niobrara farther south. This flora is probably continued 

 along the Rocky Mountain region by that of the Mill Creek series, 

 which, however, has more the aspect of that of the Dakota period. 

 {Op. cit., 1885, part iv., p. 11.) It is less rich in cycads and conifers, 

 and has species of Platanus, Macclintockia, Cinnamomnm, Laurus, Mag- 

 nolia, and Aralia. The aggregate of the Dunvegan and Mill Creek 

 series may thus be regarded as Middle Cretaceous or Cenomanian 

 and Senonian, and corresponding in the main to the Atane of 

 Greenland. It belongs to the northern and western sides of the 

 same great Cretaceous mediterranean sea on whose shores the 

 previous Kootanie flora had flourished. 



East of the Rocky Mountains this is succeeded by prevalent 

 marine conditions, with the local interposition of the Belly River 

 series, which contains beds of coal, but so far a meagre flora, including 

 Sequoia Reichenhachii, Brasenia antiqua, Trapa horcalis, and species of 

 Acer and Populus. 



Passing across the mountains to the Pacific coast, we meet with 

 the abundant and interesting flora of the Cretaceous Coal-measures 

 of Vancouver Island, a truly Upper Cretaceous assemblage. It 

 evinces a still warmer climate than those previously noted, or than 

 the succeeding Laramie ; but it is not improbable that already some 

 difference existed in this respect between tlie Pacific coast and the 



