;6o 



NEW YORK STATE MUSEUM 



Norton's Landing, 229. 

 Notre Dame mountains, 15. 

 Nouvelle river, 89. 

 Nucleospira, 88. 



ventricosa, 34, 35, 46, no, 175, 247. 

 Nuculites, 44. 



sp., 162, 246. 



explanation of plate, 300. 



triquetrus, 85, 233, 246. 

 explanation of plate, 300. 



Odontocephalus, 132. 



selenurus, see Dalmanites (Odontoce 

 phalus) selenurus. 



Odontochile, 132, 133. 



Oehlert, cited, 127, 129. 



Ohio, fossils, 198. 



Oil, 91-93. 



Oiseau, Cape, 82. 



Old Red sandstone, 87. 



Onchus, 80. 



Onondaga limestone, fauna, 123, 126, 127 

 139, 140, 146, 148, 160, 162, 163, 174 

 179, i8i, 184, 186, 198, 201, 209, 211 

 215, 217, 228, 238, 240, 243, 251. 



Ontario, 191, 198, 201. 



Orbiculoidea, 44, 249. 

 sp., 213. 



explanation of plate, 347. 

 bella, 38, 1 16, 249. 



explanation of plate, 347. 

 jervisensis, 213. 

 montis, 44 213, 249. 



explanation of plate, 347. 

 schucherti, 65, 66. 



Oriskanian formation, 7, 86, 117; fossils 

 118, 121, 123, 125, 132, 140, 144, 146 

 149, 155. i5^-. 157. 159- 163, 164, 165 

 166, 168, 169, 170, 171, 172, 173, 174 

 175, 176, 177, 180, 181, 182, 183, 184 

 191, 194, 200, 201, 205, 210, 211, 212 

 213, 226, 227, 233, 236, 238, 241, 242 



243. 250- 

 Oriskany Falls, 149. 



Oriskany period, 8-10; fauna: elements of 



next succeeding geologic age in, 10. 

 Oriskany sea in New York, illus., g. 

 Orthis, 83. 



allied to O. vanuxemi, 89. 



(Rhipidomella) ?, 203. 



sp., 26, 27, T,^,. 



aurelia, 33, 89, 198. 



aymara, 174. 



discus, 112, 205. 



dubia, 203. 



glypta, 198. 



hipparionyx, 200. 



lepidus, 242. 



livia, 201, 202. 



loveni, 198. 



lucia, 204. 



merope, 72. 



musculosa, 201. 



oblata, 27, 201, 202. 



pectinella, 198. 



planoconvexa, 205. 



subcarinata, 112. 

 Orthoceras, t,^^, 34, 38, 43, 83, 244. 



sp., 26, 27, 28, 142. 

 Orthonychia belli, see Platyceras (Ortho- 



nychia) belli. 

 Orthostrophia canadensis, 34, 36, 112, 248. 

 explanation of plate, 338. 



halli, 112. 



strophomenoides, 112. 

 Orthothetes, 242. 



arctostriata, 199. 



(Schuchertella) becraftensis, 45, 85, 86, 

 199, 238, 248. 

 explanation of plate, 334. 



deforrnis, 199. 



(Schuchertella) Avoolworthanus, 34, 36, 

 112, 248. 

 explanation of plate, 334. 

 mvU. gaspensis, 45, 199-200, 248. 

 explanation of plate, 334. 

 Ortonia, 71. 



sp., 60. 



