8 



C O N T R I B U TI O N S TO PAL^ONTOLOGY 



includes all but the basal 475 feet of what has hitherto been termed the "Laramie" 

 formation. The "Laramie" has previously been separated by a persistent con- 

 glomerate from the overlying Post-" Laramie " (Fort Union?) formation. The 

 vaUdity of the Post-" Laramie " formation as a separate Mthologic unit has as yet 

 not been fuUy corroborated by fossil evidence. 



The changes in the interpretation of the stratigraphic sequence in this region 

 are shown in Figure 3. The formations below the Mesaverde group and above the 

 Wasatch formation have been omitted as irrelevant to the present problem. 



* Hancock'B section did not include the Poat-" Laramie " and Wasatch formationa. 



FiQ. 3 — Late Cretaceous and early Tertiary formations in northwestern Colorado. 



