WHITE.] FOSSILS OF THE CACHE A LA POUDEE. 175 



made, and consequently the aggrefjate thickness of them is not IcnoAvn. 

 This thickness, ho"\vevcr, is osthuated to be about 250 feet between 

 Marck's faini and a point about lour miles above Eaton's farm. 



At the exposures here referred to the following list of fossils was col- 

 lected, all belonging- to the extreme upper portion of the Cretaceous 

 series beneath the Laramie Group. A part of them also characterize 

 the highest known Cretaceous strata beneath the Judith River Group 

 in the Upper Missouri River region, as shown by Meek and Hayden, 

 but the relations of those fossils in this respect will be discussed in con- 

 nection with those collected at Fossil Creek, Little Thompson Creek, 

 the mouth of the Saint Vrains, &c., because the strata exi)osed at these 

 localities all belong to one natural group. 



LIST OF THE FOSSILS COLLECTED FEOM CRETACEOUS STEATA IN THE 

 VALLEY OF THE CACHE 1 LA POUDEE, FEOM FIVE TO TWELVE 

 MILES WEST OF GEEELEY, COLOEADO. 



1. Fragments of fossil wood. 



2. Pferia [Oxytoma) nehrascana Evaijs & Shumard. 



3. Nticula cmicellata Meek & Hayden. 



4. Wiicula plcmimarginata Meek & Hayden. 



5. Tancredia americana Meek & Hayden. 

 C. YenieUa humilis Meek & Hayden. 



7. Cardium speciosum Meek «& Hayden. 



8. Tcllina scitula Meek & Hayden. 



9. Maetra {Cymhophora) formosa Meek & Hayden. 



10. Maetra [Gym'boplwra) alta Meek & Hayden. 



11. Dentalium gracile Hall & Meek. 



12. CyUcJina scitula Meek & Hayden. 



13. Lunatia moreaiiensis Meek & Hayden. 



14. Anchura, ? 



15. Fasciolaria {Piestoclieilus) cuJhertsoni Meek & Hayden. 



16. Flacenticeras lenticulare Owen sp. 



Leaving the valley of the Cache a la Poudre at a point about four 

 miles west of Aaron Eaton's farm, I went more directly westward toward 

 the mountains. Search was made in this region for the line of junction, 

 or plane of demarkation between these Upper Cretaceous strata and the 

 base of the Laramie Group. In consequence of the great prevalence of 

 the debris of the j^lains, which has already been referred to, I was not 

 successful in this search, although it is quite evident that the lower strata 

 of the Laramie Group occupy the upper part of the slope of the valley 

 side, as well as the higher lands of the region on both sides of the valley. 

 Higley's coal-mine, which has been already mentioned, is opened in 

 Laramie strata in the upper part of the long, low, sloping, opposite 

 valley-side, and its position is thus shown to be not far above these Cre- 

 taceous strata, and consequently near the base of the Lai-amie Grou^). 

 But this subject will be taken up again on a subsequent page. 



Proceeding westward after leaving the valley of the Cache a la Poudre, 

 I found no exposures of rock until I reached Fossil Creek, about two 

 miles east of the base of the foot-hills of the Rocky Mountains. Along 

 a ridge havmg the local name of "Fossil Ridge," which runs southward 

 from this creek three or four miles parallel with the foot-hills, there are 

 considerable exposures of coarse sandstoiies containing fossils that 

 characterize the upper series of Cretaceous strata, known in the Upper 

 Missoiui River region as the Fox Hills and Fort Pierre Grouijs. From 



