GEOLOGICAL SURVEY OF THE TERRITORIES. 295 



both districts they contain lignite, and are succeeded by later tertiary 

 beds of strictly fresh-water origin. 



The fossils from the later tertiary deposits of Wyoming and Utah, 

 mentioned in the lists, came from Henry's and Black's Forks of Green 

 Eiver, Church Buttes, Barrel Springs, Fort Bridger, Pacific Springs, 

 and other localities of the same region. They belong to the genera 

 Unio, Sphcerium, Goniobasis, Bythinella, Physa, Planorbis, &c, most of 

 which are very numerous in individuals, though there are not many 

 species of any one of these genera. From the entire absence of marine 

 and brackish-water types in these beds, it seems evident that they were 

 deposited in fresh-water lakes, entirely isolated from the influx of tides, 

 in basins that were raised above the level of the sea, in part by the ac- 

 cumulation of sedimentary deposits, and probably in part from .the grad- 

 ual elevation of the whole country. These later beds may be susceptible 

 of subdivision into several subordinate groups, but the fossils yet known 

 show closer relations between the different beds of this series than be- 

 tween any of them and the brackish-water deposits beneath. Indeed, I 

 have not been able to identify a single species from the latter with any 

 of those from the strictly fresh- water beds under consideration, and they 

 are also equally distinct from all of those known from the Upper Mis- 

 souri country. 



From the differences observable between the species found in these 

 fresh-water deposits and the older brackish-water beds of the same re- 

 gion, believed to belong to the eocene, and the superposition of the for- 

 mer, it is reasonable to infer that the later series belongs wholly or 

 mainly to the horizon of the miocene, especially as none of the fossils 

 contained in these beds are certainly known to belong to existing spe- 

 cies. 



LISTS OF FOSSILS COLLECTED. 

 SILURIAN SPECIES. 



1. Ort Ms desmopleura, Meek 1 ; Colorado City. 



2. Meristella or Merisia (undetermined species) ; Crater's Falls. 



3. OpMleta eomplanata, var. nana ; Crater's Falls. 



4. Bucanella nana, Meek 2 ; Crater's Falls. 



5. BapMstoma ; Crater's Falls. 



6. Encloceras (undetermined species) ; Crater's Falls. 



CARBONIFEROUS SPECIES. 



1. Fusulina cylindrica, Fischer ; Moleen Station. 



2. Syringopora (undetermined specimen); Moleen Station. 



3. Campophyllum, like C. torquium, Owen ; Hot Springs, Salinas Creek, Salt Lake. 



4. Zaphrentis (?); Head Black Fork Bear River, Utah. 



5. Crinoid columns ; Pecos Church, Mora Creek, and Hot Springs. 



6. Chcetetes (undetermined massive and ramose forms); Moleen Station, Salinas 

 Creek. 



7. Fenestella and Polypora ; near Pecos Range, 10 miles south of Kosylowiski, New- 

 Mexico, and Mora Station. 



8. Synocladia (Septopora) Cestriensis, Prout (sp.); Mora River. 



9. Ortliis (undetermined species) ; Santa F6, New Mexico. 



10. Hcmipronites crassus, M. and W.; Santa Fe" 5 New Mexico, Box Elder Caiion, North 

 Platte. 



11. Chonetes (undetermined species) ; Santa F6, New Mexico, Box Elder Caiion. 



12. Productm Ncbrascensis, Owen ; Moleen Station, Santa F6, New Mexico. 



13. Productus punctatus, Martin, (sp.) ; Sangre de Christo Pass, Colorado. 



1. I proposed for this species the name O. Coloradoensis, in the Proceed. Am. Philosoph. Soc, xi, p. 

 425, 1870 ; but as Dr. Shumard had previously used that name for another species of this genus, it he- 

 comes necessary to make a change. 



2. Proceed. Am. Philosoph. Soc, xi, p. 426, 1870. 



