122 G. M. Dawson — Earlier Cretaceous Rocks 



The purpose of the present note is to call attention to cer- 

 tain facts recently developed respecting the equivalency of the 

 Queen Charlotte Islands and Kootanie formations and to the 

 importance of the earlier Cretaceous rocks of which they are 

 representatives, over great areas of the western and extreme 

 northwestern portion of the continent. These facts possess 

 particular interest at the present time from their analogy to 

 those lately developed by Mr. R. T. Hill respecting a similar 

 earlier Cretaceous formation in the southwestern region of the 

 United States.* 



The region in which the Kootanie was first recognized as a 

 distinct lower portion of the Cretaceous, embracing that por- 

 tion of the Rocky Mountains above defined, with, the adjacent 

 foot-hills, has a length of about 140 miles with a width of 

 forty miles or more. The Kootanie formation here constitutes 

 a great part of the area of the several Cretaceous troughs or 

 infolds and comes to the surface as well in several or many 

 places in the foot-hills to the east. The Cretaceous rocks of 

 this part of the mountains are known to extend upward from 

 the Kootanie so far as to include the base of the Laramie. 

 The thickness of the upper members of the series has not been 

 ascertained, but that of the Benton (possibly including part of 

 the Niobrara) is about 1400 feet, while the maximum known 

 thickness of the lower part of the series, referable to the 

 Dakota and Kootanie, is about 11,950 feet. Of this thickness, 

 over 7000 feet is shown by its fossils to belong to the 

 Kootanie, while the line between this formation and the 

 Dakota remains to be drawn in a series of beds above, from 

 which no fully distinctive fossils have been collected.f 



In the report for 1885, above cited, it is stated that one of 

 the characteristic fossil plants of the Kootanie had previously 

 been found in northern British Columbia, at a distance of 580 

 miles to the northwestward of the part of the Rocky Mountains 

 there under description. The flora of the Kootanie was char- 

 acterized as Lowest Cretaceous and placed on approximately 

 the same horizon with that of the Queen Charlotte Islands 

 formation (more particularly of subdivision C, of that section) 

 by Sir J. Win. Dawson.;}: 



Up to this time no recognizable fossils other than plants had 

 been obtained from the Kootanie, but marine mollusks have 

 since been discovered by Mr. R. G. McConnell in beds which 

 are (at least locally) at the very base of the formation and 

 which underlie the principal plant-bearing beds by at least 

 several hundred feet. These are referred to in Mr. McCon- 



* See this Journal, vol. xxxiii, p. 291 ; vol. xxxiv, p. 287 ; vol. xxxvii, p. 282. 

 f Though fossil plants apparently referable to the Dakota have been found in 

 the higher beds, in two places. 



\ Trans. Royal Soc. Can., vol. in, sec. 4, p. 20. 



