THE STRATIGRAPHICAL POSITION OF THE LARAMIE. 283 



Professor L. F. Ward*, in his historical review of the opinions held iu re- 

 gard to the Laramie group, seems to regard the point of view assumed by 

 Mr. King in summarizing the evidence on this subject as puerile ; neverthe- 

 less I am convinced that much of the confusion that has obtained in the 

 minds of palaeontologists in regard to the proper position of these beds in the 

 geological column would have been avoided had they possessed an accurate 

 knowledge of the stratigraphical relations of the beds of each locality from 

 which their fossil evidence was obtained. 



No one has done more to reconcile the opposing views and clear up this 

 confusion than Dr. C. A. White, who has combined in his work the qualities 

 of the structural geologist with those of the palaeontologist. In his recent 

 review of the North American Mesozoic f he says : 



" The formations which overlie the Laramie were, by common consent, long ago re- 

 garded as of Tertiary age; but concerning the age of some of them, differences of 

 opinion have since arisen. Between the Laramie and any overlying formation there 

 is often, but not always, unconformity. In Utah, and apparently in the valley of the 

 Yellowstone also, I have found the Laramie passing gradually up into purely fresh- 

 water deposits without any stratigraphical break. In the former case I am sure, and 

 in the latter case I believe with Professor Newberry, that the upper strata represent 

 the lower part of the Wasatch group." 



Without knowing more about the locality referred to than is here ex- 

 pressed, I should not consider, from a stratigraphical standpoint, that this 

 disproved in any degree the unconformity, and the orographic movement 

 which that implies, between the Laramie and the Wasatch ; since in the 

 broader depressions away from the immediate vicinity of a line of disturb- 

 ance the succeeding beds, even after a physical break, may be expected to 

 be found quite conformable with those below them. As regards continuance 

 or non-continuance of certain forms of life across such a break, I do not 

 wish to invade the province of the biologist in offering an opinion, but 

 would merely suggest that the probable persistence of land areas of some 

 kind throughout the various orographic changes that have occurred in this 

 region, which I have here insisted on, would seem to be of some importance 

 in explaining survivals here wdiich are unusual in other regions. 



As regards the coal-bearing Laramie in the Rocky Mountain region, which 

 I have hitherto spoken of as the Laramie proper, it has now been examined 

 more thoroughly than any other formation on account of its economic im- 

 portance, and those who have carefully studied it in one locality find no 

 difficulty in recognizing it in others, in spite of local variations in character 

 of sediment and thickness of beds. Its exact relation to the beds which 

 have been deposited upon it since the movement in question are, however, 



* Synopsis of the Laramip Flora: Sixth Ann. Rep. Director U. S. Geol. Survey, Washington, I881 

 t Proc. A. A. A. S., Vol. XXXVIII, Aug.. 1S89. 



