WHITE.) GROUPS OF STRATA. 21 



of those deposits on both sides of the Uinta Mountains has left no doubt 

 on my mind of their identity. I therefore adopt Mr. King's name ■•' Uinta 

 Group," instead of Professor Powell's name "Brown's Park Group." 



While adopting the name "Colorado Group" of Mr. King, I, for pale- 

 on tological reasons chiefly, so restrict its application as to include only 

 what I understand to be equivalent with Nos. 2 and 3 of Meek and Hay- 

 den's original section, leaving the equivalent of No. 4 to be included 

 with the strata of the Fox Hills Group, instead of with the Colorado 

 Group, as Mr. King has done. 



The following table of general sections, as may be seen at a glance, 

 is designed to show the correlation of the different groups named by the 

 several authors, as I understand them. The first column represents the 

 section that was many years ago prepared by Messrs. Meek and Haydea 

 for the Mesozoic rocks of the Upper Missouri River region ; the second 

 embraces the names of the Tertiary and Post- Cretaceous Groups of 

 Wyoming, Colorado, and Utah that have, from time to time, been proposed 

 by Dr. Hayden ; the third has been compiled from Mr. King's map of 

 the Green Eiver Basin, that has already been referred to ; the fourth 

 is the classification proposed by Professor Powell in his Report on the 

 Geology of the Uinta Mountains ; and the fifth is the classification of the 

 rocks of this district which I have adopted in this report. 



