70 SIE W. DAWSON 



cies collected by Mr. McCouuoll, aud which certaiuly represent the more abundant trees 

 of the region in this period. 



The matrix of most of the plants is a light-coloured shale or indurated clay, resem- 

 bling that of the Laramie iu many other localities. In the case of some slabs, however, 

 the heat of burning lignite has converted the clay into a sort of terracotta of reddish and 

 yellowish colours. 



In the present paper I shall refer merely to the geographical distribution of the spe- 

 cies in connection with the evidence for the Laramie age of the Mackenzie River beds, 

 which will be described more in detail by Mr. McConnell in his forthcoming Report. 



Pteris Sitkensis, Heer. (PI. X, Fig. 1.) — This fern, not previously collected on the 

 Mackenzie, was originally collected near Sitka in Alaska, and constitutes another 

 link of connection between the flora of the Pacific coast and that of the interior 

 region iu the early Eocene age. 



Glyptostrobus UnctERI, Heer. — If this species be the same with G. Europœus and G. 

 Œningensis, which seems probable, it is very widely distributed in Europe and 

 America. It is found in Alaska, Greenland and Spitzbergen ; also iu the Upper 

 Laramie of Porcupine Creek (G. M. D.) aud in the Fort Union group of Dakota. 

 (Newberry). 



Sequoia L.4.ngsdorfii, Brongt. — This species is A'ery widely distributed iu time and 

 space, if all the forms referred to it are really of one species. It ranges from the 

 Upper Cretaceous into the Miocene, and in reality is not very remote in its char- 

 acters from the living Sequoia sempervirenx of California, which may be a modern 

 variety. It occiirs in Greenland, in the Laramie of various places iu the United 

 States, aud is widely distributed iu Europe. Both leafy twigs and remains of 

 cones occur in the Mackenzie collections. In the Belly River Group of Canada, 

 the species S. Reicheubachii ' replaces it, and the species referred to S. Langsdorfii from 

 the Upper Cretaceous of Nanaimo, VancouA'er Island, appears to be /S. Smilhkma, ' 

 which also occiirs iu the Kootauie of the Rocky Mountains. It seems therefon^ 

 uncertain if in Canada it is as old as the Cretaceous, and it may iu any case be 

 regarded as specially characteristic of the Upper Laramie or Eocene flora. 



Taxites Olriki, Heer. — This large aud beautiful Taxine plant occurs in the Eocene of 

 Europe, and is found also in Alaska and iu Greenland. It is abundant in the 

 collections of Dr. Selwyn from Souris River, described by me in the Report of the 

 Geological Survey of Canada (1879-80). '' It does not seem as yet to have been 

 recognized in the United States, and is probably a distinctively northern form. It 

 is said by Schimper to resemble closely a species of Cephalotaxus found in China 



• and Japan. 



PL.4.TANUS ACEROIDES, Heer. — This is the Eocene representative of the mod(n-n Platanus 

 occidentalia of America, to which it is very nearly allied. It occurs in the Tertiary 



' Flora of Cretaceous of British Columbia and Northwest Territory, Trans. R. S. C, 18S2. 

 2 Mesozoic Flora of Rocky Mountains, Tran.s. R. S. C, 18S5. 

 " Fossil Plants of Laramie, Trans. K. S. C, ISSG. 



