Mussel-shell river, 69, 77. 
Myalina, 40. 
Mylognathus, 101. 
Mytilide, 89. 
Mytilites, 89. 
Mytilus, 22, 89. 
Natica, 84. 
Naticopsis, 46. 
Naticide, 84. 
Nautilide, 81. 
Nautilus, 50, 66, 69, 81. 
Necera, 87. 
Nebraska, conclusions about, 11. 
Neritopsis, 85. 
New Mexico, 38. 
Newberry, Dr., 123. 
Neuwied, Prince of, 2. 
Nice, 180. 
Nicollet, report of, 2. 
Nicollet on Pseudo Volcanic Phe- 
nomena, 79. 
Niobrara, sandhills of, 15. 
Norwood, Dr., 38. 
Norwood, Dr., in regard to Permian 
beds in Illinois, 55. 
North Platte, 15. 
Nucleus of mountain ranges, 117. 
Nucula, 90. 
Nuculide, 91. 
Obolus, 23, 37. 
O’Fallon’s creek, 97. 
Ogden ferry, 51. 
Old Woman’s branch, 19, 20. 
Omadi, 10. 
Omaha City, 10. 
Omaha Mission, 9. 
Opening creek, 80. 
Oregon, 131. 
Oreodon, 14, 106. 
Oreodon Culbertsoni, 14. 
Orthisina, 40. 
Osawkee, 42. 
Ostrea, 91, 1038. 
Ostreade, 91, 103. 
Ostrea congesta, 10, 91. 
Otoe Village, 6. 
Owen, Dr. D. D., 3. 
Pacific Railroad reports, 37. 
Pacific coast, 115. 
Paleocherus, 106. 
Paleolagus, 107. 
Paludina, 102, 105. 
Panopea, 72. 
VOL. XII.—28 
OF THE UPPER MISSOURI. 
Papillion creek, 6. 
Parahippus, 106. 
Patent Office report, 131. 
Pawnee Village, 11. 
Pebbles, water-worn, 31. 
Pecten, 91. 
Pectenide, 91. 
Pectunculina, 90. 
Pectunculus, 10, 90. 
Pentacrinus, 25, 128. 
Permian, 33, 34, 38, 55. 
Permian fossils, reference to, 53. 
Petalodus, 51. 
Pharella, 73. 
Pholadide, 86. 
Pholas, 10, 86. 
Pholodomya, 87. 
Physa, 102. 
Pierre’s hole, 119. 
Pillsbury, Mr., 48. 
Pike’s Peak, 118. 
Pinau’s spring, fresh-water shells 
of, 14. 
Pinna, 45. 
Planarian worms, trails of, 25. 
Planorbis, 3, 102. 
Plastic clay, with fish remains and 
other fossils, 21. 
Platte Valley, 5. 
Platte, Lower, 7. 
Platte river, 5. 
North Platte, 118. 
Platte country, 4. 
Plewrophorus, 50. 
Pleurotoma, 84. 
Pleurotomaria, 22, 66. 
Pliocene, 13, 105. 
Pebrotherium, 106. 
Polygyra, 102. 
Popo Agie, 119. 
-Porcupine river, 77. 
Post Pliocene marls, 11, 13. 
Post Pliocene, 12, 104. 
Potsdam sandstone, 16, 26. 
Potsdam sandstone, conglomerate 
character, 26. 
Potamomya, 103. 
Powder river, 116. 
Procamelus, 106. 
Productus, 5, 6, 16, 62. 
Promontory Point, 37. 
Protohippus, 107. 
Protomeryx, 106. 
217 
Prout, Dr. H. A., 3. 
Pseudobuccinum, 8+. 
Pseudelurus, 107. 
Pterophyllum, 123. 
Ptychoceras, 83. 
Pyrula, 84. 
Quaking Asp river, 77. 
Quaternary deposits, 42, 107. 
Quartz, white, 35. 
Quensted, Prof., 68. 
Radiata, 91. 
Rawhide Butte creek, 15. 
Raynolds, Captain Wm. F., 114. 
Red arenaceous beds, 117. 
Red buttes, 118. ; 
Remains, vertebrate, in superficial 
deposits, pliocene, 18, 110. 
Remains, mammalian and chelo- 
nian, 3, 104, 106, 107. 
Republican river, 58. 
Retzia Mormoni, 16, 64. 
Rhinoceros, 106. 
Rhynconella uta, 16, 63. 
Richardson, Sir John, 36, 99. 
Ridges of elevation, Black Hills, 21. 
River terraces, 112, 113. 
Rocks, trappean, 34. 
Rocks, granite, stratified, azoic, and 
eruptive, 33. 
Rodentia, 107. 
Reemer, Dr., 64. 
Rogers, Prof., 3. 
Rostellaria, 84. 
Round Butte, 77, 97. 
Ruminantia, 106. 
Russia, fossils from, 38. 
Sabal lamononis, 180. 
Sage creek, 4, 29. 
Saline substance, analysis of, 76. 
Sandstone, gray, 20. 
Sandstone, micaceous, 6. 
Sandstone, ferruginous, 8. 
Sandstone quartzose, 16. 
Sandstone, red, No. 1, 9. 
Sandstone, Potsdam, of Black Hills, 
7. 
Sandstone, white, 25. 
Sandstone Potsdam, 20. 
Sandhills, notice of, 15. 
Santa Fe road, 39. 
Sarpy, P. A., trading post, 5. 
Saskachewan, 36. 
Saurian bones, 28. 
