Section IV., 1885. [ 1 ] Trans. Roy. Soc. Canada. 



I. — 0)1 the Meso?:olc Floras of the Bochy Mountain Region of Canada. 

 Bij Sir J. William Dawson, C.M.a., LL.D., F.R.S. 



(Presentod IMay 27, 188.5.) 



In a paper read before this Society in 1883, and published in the fir.st volnme of its 

 Transactions, I noticed the Cretaceous and Tertiary floras of British Columbia and the 

 Northwest Territories, known up to that time, and described the new species which they 

 had afforded. The lowest Cretaceous flora, that of the Queen Charlotte Islands, has a 

 strictly Mesozoic aspect and affords no Dicotyledonous plants. That of the Dunvegan 

 group on Peace River, on the contrary, abounds in Dicotyledons, and may be regarded 

 as a Middle Cretaceous flora of the age of the Niobrara group or Cenomanian, and is warm- 

 temperate or sub-tropical. The assemblage of plants associated with the coal beds of 

 Vancouver is distinctly Upper Cretaceous, and in its generic forms has a very modern 

 aspect and a decidedly warm-temperate character. A still newer flora is that of the 

 Laramie series, which may be regarded as a transition group connecting the Upper Creta- 

 ceous with the Eocene, and is still warm-temperate in its aspect, though differing in its 

 specific, and to some extent in its generic forms. 



The material at that time in my hands showed nothing from the Rocky Mountain 

 region certainly Lower Cretaceous, and nothing between the Queen Charlotte series and 

 that of Peace River to fill up the great gap separating these very distinct groups of 

 plants, except a small collection from Suskwa River and Willow Creek, containing 

 the species which I named Dioonites borealis, Pinm Suskwaensis and Laurus crassinervis. 

 These I believed to indicate an horizon lower than that of the Dunvegan group of Peace 

 River, but this could not at the time be regarded as certain. 



In the past summer considerable collections have been made by Dr. Ci. M. Dawson, 

 from troughs of Mesozoic rocks included in the older formations of the Rockies, and which 

 show the existence there of a series of fossil plants whose affinities with those of other 

 regions would entitle them to be called Jurasso-Cretaceous. They consist of ferns, 

 cycads and conifers, some of them identical with, or closely allied to, those of the Juras- 

 sic of the Amur country in Siberia, and others similarly related to those of the Lower 

 Cretaceous of Greenland, as these floras have been described by Heer. This group, 

 undoubtedly, represents the flora of the Lowest Cretaceous, which has not hitherto been 

 recognized in Western America, and will form a sure basis from which to trace the devel- 

 opment of the vegetable kingdom upward to its more modern forms. Unfortunately, a 

 considerable thickness of beds overlying those holding these more ancient plants, has 

 afforded no fossils, and the next beds in ascending order which afford plants contain, in 

 addition to survivors of the older flora, a few new forms belonging to the Dicotyledo- 



Sec. IV., 1S85. 1. 



