Nassa, 293.
Natatores, 297.
Natica, 271, 293.
Nautilus, 112-114, 130, 149, 186, 199, 237, 272, 294; Danicus, 272; pompilius, 237.
Neanderthal skull, 364.
Neocomian series, 257, 260.
Neolimulus, 125.
Nerinœa, 237, 271; Goodhallii, 237.
Nerita, 393.
Neuroptera, 311.
Neuropteris, 136.
Newer Pliocene, 323, 324.
New Red Sandstone, 193, 203.
Newts, 189, 200, 217.
Niagara Limestone, 117.
Nipadites, 290; ellipticus, 290.
Nœggerathia, 197.
Norwich Crag, 324.
Nothosaurus, 219; mirabilis, 219.
Notidanus, 241.
Numenius gypsorum, 297.
Nummulina, 172, 290; lœvigata, 290; pristina, 172.
Nummulitic Limestone, 24, 287, 291.

Oak, 262, 310.
Obolella, 87; sagittalis, 88.
Odd-toed Ungulates, 300, 315, 327, 353.
Odontaspis, 275.
Odontopteris, 165; Schlotheimi, 164.
Odontopteryx, 297; toliapicus, 297, 298.
Odontornithes, 282.
Ogygia, 108; Buchii, 107.
Older Pliocene, 323, 324.
Oldhamia, 81; antiqua, 82; slates of Ireland, 79, 80.
Old Red Sandstone, 133; origin of name, 133; of Scotland, 134; relations of, to Devonian, 133, 134, 155.
Olenus, 108; micrurus, 88.
Oligocene, 305.
Oligoporus, 178.
Olive-shells, 293.
Omphyma, 119.
Onchus, 130; tenuistriatus, 131.
Oneida Conglomerate, 116.
Onychodus, 153; sigmoides, 151.
Oolitic limestone, structure of, 28; mode of formation of, 30.
Oolitic rocks (see Jurassic).
Ooze, Atlantic, 22, 33.
Ophidia, 251; of the Eocene, 296.
Ophiuroidea, of the Lower Silurian, 105; of the Upper Silurian, 120; of the Carboniferous, 177; of the Trias, 210; of the Jurassic, 233.
Opossum, 299, 315.
Orbitoides, 291.
Oriskany Sandstone, 135.
Ormoxylon, 138.
Orohippus, 302.
Orthis, 38, 109, 125, 147, 184, 199; biforata, 109; Davidsoni, 127; elegantula, 127; flabellulum, 109; Hicksii, 38; lenticularis, 38; plicatella, 110; resupinata, 185; subquadrala, 109; testudinaria, 110.
Orthoceras, 89, 112, 113, 130, 149, 186, 213; crebriseptum, 113.
Orthonota, 111.
Orthoptera, 182, 311.
Osmeroides, 276; Mantelli, 276.
Osmerus, 276.
Ostealepis, 153.
Ostracode Crustaceans of the Cambrian, 83; of the Lower Silurian, 107; of the Upper Silurian, 123; of the Devonian, 145; of the Carboniferous, 179; of the Permian, 197; of the Trias, 210; of the Jurassic, 233; of the Cretaceous, 267.
Ostrea acuminata, 235; Couloni, 269; deltoidea, 235; distorta, 235; expansa, gregarea, 235; Marshii, 235, 236.
Otodus, 295; obtiquus, 296.
Otozamites, 230.
Otozoum, 206.
Oudenodon, 220; Bainii, 221.
Ovibos moschatus, 356.
Oxford Clay, 227, 229.
Oxyrhina, 312; xiphodon, 313.
Oysters, 235, 236, 269.

Pachyphyllum, 173.
Palœarca, 111.
Palœaster, 120; Ruthveni, 121.
Palasterina, 120; primœva, 121.
Palœchinus, 120, 178; ellipticus, 177.
Palœocaris, 180; typus, 180.
Palœocoma, 120; Colvini, 121.
Palœocoryne, 172.
Palæolithic man, remains of, 363-365.
Palœomanon, 118.
Palœoniscus, 188, 200.
Palœontina Oolitica, 233.
Palæontological evidence as to Evolution, 60, 372-374.
Palæontological record, imperfection of the, 50, 51.
Palæontology, definition of, 10.
Palœonyctis, 304.
Palœophis, 296; toliapictus, 296; typhœus, 296.
Palœoreas, 318.
Palœosaurus, 200, 218, 219; platyodon, 219.
Palœosiren Beinerti, 200.
Palœotherium, 300; magnum, 301.
Palœoxylon, 170.
Palæozoic period, 44.
Palms, 230, 263, 290, 308, 309.
Paludina, 257, 294.
Pandaneœ, 230.
Pandanus, 262.
Paradoxides, 86, 87, 108; Bohemicus, 85.
Parasmilia, 266.
Parkeria, 264.
Pear Encrinite, 231.
Pearly Nautilus, 58, 111, 112, 237.
Peccaries, 317.
Pecopteris, 136, 165, 196.
Pecten Grœnlandicus, 338; Islandicus, 338; Valoniensis, 211, 212, 204.
Penarth Beds, 204.
Pennatulidœ, 292.
Pentacrinus, 231; caput-medusœ, 231; fasciculosus, 232.
Pentamerus, 125, 126; galeatus, 126; Knightii, 128.
Pentremites (see Blastoidea).
Pentremites conoideus, 176; pyriformis, 176.
Perching Birds, 297.
Percidœ, 276.
Periechocrinus, 122.
Perissodactyle Ungulates, 300, 315, 327.
Permian period, 192-202; rocks of, in Britain, 194; in North America, 194; life of, 195-302.
Persistent types of life, 58, 371.
Petalodus, 188.
Petraster, 120.
Petroleum, origin of, 36.
Pezophaps, 348.
Phacops, 108, 123, 145; Downingiœ, 124; granulatus, 144; lœvis, 144; latifrons, 144, 145; longicaudatus, 124; rana, 145.
Phœnopora ensiformis, 126.
Phalangers, 348.
Phanerogams, 164.
Phaneropleuron, 153.
Phascolotherium, 253, 254.
Pheronema, 164.
Phillipsastrœa, 142.
Phillipsia, 179; seminifera, 180.
Pholadomya, 235.
Phormosoma, 178.
Phorus, 271.
Phosphate of lime, concretions of, 30; disseminated in rocks, 30; origin of, 31.
Phyllograptus, 102; typus, 102.
Phyllopoda, of the Cambrian, 83; of the Lower Silurian, 108; of the Upper Silurian, 123; of the Devonian, 145; of the Carboniferous, 179; of the Permian, 197; of the Trias, 210.
Phyllopora, 210.
Physa, 294; columnaris, 294.
Pigs, 302, 317, 329, 354.
Pilton Group, 135.
Pinites, 170.
Pisces (see Fishes).
Pisolite, 29.
Pisolitic Limestone of France, 259, 286.
Placodus, 220; gigas, 220.
Placoid Fishes, 150; of the Upper Silurian, 130, 131; of the Devonian, 153-155; of the Carboniferous, 188; of the Permian, 199; of the Trias, 214; of the Jurassic, 241; of the Cretaceous, 275; of the Eocene, 295; of the Miocene, 312.
Plagiaulax, 254.
Planolites, 122; vulgaris, 123.
Planorbis, 294.
Plants, of the Cambrian, 80, 81; of the Lower Silurian, 97, 98; of the Upper Silurian, 118; of the Devonian, 136-139; of the Carboniferous, 163-170; of the Permian, 196; of the Trias, 207, 208; of the Jurassic, 229, 230; of the Cretaceous, 261-263; of the Eocene, 289, 290; of the Miocene, 308-311.
Plasmopora, 119.
Platanus, 262, 308; aceroides, 309.
Platephemera antiqua, 145.
Platyceras, 128, 148; dumosum, 148; multisinuatum, 129; ventricosum, 129.
Platycrinus, 122, 175; tricontadactylus, 175.
Platyostoma, 129; Niagarense, 129.
Platyrhine Monkeys, 362.
Platyschisma helicites, 129.
Platysomus, 200; gibbosus, 199.
Platystoma, 213.
Pleistocene period; climate of.
Plesiosaurus, 334; dolichodeirus, 244.
Pleurocystites squamosus, 106.
Pleurotoma, 293.
Pleurotomaria, 111, 129, 186, 199, 236, 271.
Plicatula, 213.
Pliocene period, 323; rocks of, in Britain, 324; in Belgium, 325; in Italy, 325; in North America, 326; life of, 326-331.
Pliopithecus, 322; antiquus, 323.
Pliosaurus, 245.
Podocarya, 230.
Podozamites, 208; lanceolatus, 209.
Polir-schiefer, 33.
Polycystina, 32; of Barbadoes-earth, 33.
Polypora, 145, 184; dendroides, 183.
Polypterus, 153, 188.
Polystomella, 311.
Polytremacis, 266.
Polyzoa, of the Cambrian, 81, 89; of the Lower Silurian, 108; of the Upper Silurian, 125; of the Devonian, 145, 146; of the Carboniferous, 183, 184; of the Permian, 198; of the Trias, 210; of the Cretaceous, 267; of the Miocene, 312.
Populus, 262.
Porcellia, 186.
Porcupines, 322.
Portage Group, 135.
Port-Jackson Shark, 154.
Portland beds, 227, 229.
Post-Glacial deposits, 336, 338.
Post-Pliocene period, 334.
Post-Tertiary period, 286.
Poteriocrinus, 175.
Potsdam Sandstone, 79.
Pre-Glacial deposits, 336.
Prestwichia, 179; rotundata, 179.
Primitia, 107; strangulata, 107.
Primordial Trilobites, 85.
Primordial zone, 79.
Proboscidea, of the Miocene, 319, 322; of the Pliocene, 329, 330; of the Post-Pliocene, 357-359.
Producta, 147, 184, 198; horrida, 198; longispina, 185; semireticulata, 185.
Productella, 147, 184.
Productidœ, 147, 211.
Proëtus, 123.
Prong-buck, 318.
Protaster, 120; Sedgwickii, 121.
Proteaceœ, 262, 308, 309.
Proteus, 189.
Protichnites, 87.
Protocystites, 82.
Protornis Glarisiensis, 279.
Protorosaurus, 201, 202; Speneri, 201.
Protospongia, 81; fenestrata, 88.
Prototaxites, 118, 138; Logani, 139.
Psammobia, 292.
Psammodus, 188.
Psaronius, 136, 164.
Pseudocrinus bifasciatus, 106.
Psilophyton, 118, 137, 138; princeps, 138.
Pteranodon, 247, 277; longiceps, 277.
Pteraspis, 130, 152; Banksii, 130.
Pterichthys, 152; cornutus, 153.
Pterinœa, 128; subfalcata, 128.
Pteroceras, 237, 271.
Pterodactylus, 245, 277; crassirostris, 246.
Pterophyllum, 208, 230; Jœgeri, 209.
Pteropoda, of the Cambrian, 88; of the Lower Silurian, 111; of the Upper Silurian, 129; of the Devonian, 148; of the Carboniferous, 186; of the Permian, 199; of the Jurassic, 237.
Pterosauria, 245; of the Jurassic, 245-248; of the Cretaceous, 277.
Pterygotus Anglicus, 124, 125.
Ptilodictya, 108, 125; acuta, 109; falciformis, 109; raripora, 126; Schafferi, 109.
Ptychoceras, 273; Emericianum, 274.
Ptychodus, 275.
Pupa vetusta, 186.
Purbeck Beds, 228; Mammals of, 254.
Puryuroidea, 237.
Pycnodus, 275.
Pyrula, 293.

Quadrumana, of the Eocene, 305; of the Miocene, 322, 323; of the Pliocene, 331; of the Post-Pliocene, 361.
Quadrupeds (see Mammalia).
Quaternary period, 334.
Quebec Group, 95, 96.
Quercus, 262.

Rabbits, 322.
Rana, 313.
Raptores, 297.
Rasores, 297.
Recent period, 286, 334.
Reptaculites, 99.
Red clays, origin of, 35.
Red Coral, 311.
Red Crag, 324.
Red Deer, 336, 354.
Reindeer, 344, 345, 354, 355.
Remopleurides, 188.
Reptiles, 200; of the Permian, 200-202; of the Trias, 217-221; of the Jurassic, 242-251; of the Cretaceous, 276-281; of the Eocene, 296, 297.
Retepora, 108, 125, 145, 184, 198, 210; Ehrenbergi, 198; Phillipsi, 146.
Retiolites, 119.
Retzia, 127.
Rhætic Beds, 204-206.
Rhamphorhynchus, 247; Bucklandi, 248.
Rhinoceridœ, 315.
Rhinoceros Etruscus, 327, 328, 336, 353; leptorhinus, 328; megarhinus, 327-329, 336, 335; tichorhinus, 353, 354.
Rhinopora verrucosa, 126.
Rhizodus, 188.
Rhombus minimus, 295.
Rhyncholites, 239.
Rhynchonella, 110, 127, 147, 184, 234, 268, 292; cuneata, 127; neglecta, 127; pleurodon, 185; varians, 235.
Rhynchosaurus, 218; articeps, 218.
Rice-shells, 293.
Richmond Earth, 33, 307.
Ringed Worms (see Annelida).
River-gravels, high-level and low-level, 340, 341.
Robulina, 311.
Rocks, definition of, 14; divisions of, 14, 15; igneous, 14; aqueous, 15-18; mechanically-formed, 18-20; chemically-formed, 20; organically-formed, 20-37; arenaceous, 20; argillaceous, 20; calcareous, 20-32; siliceous, 20, 32-34.
Rodentia, of the Eocene, 305; of the Miocene, 322; of the Post-Pliocene, 361.
Roebuck, 336, 354.
Rostellaria, 237, 293.
Rotalia, 22, 98, 171, 264; Boueana, 264.
Rugose Corals, 104; of the Lower Silurian, 104, 105; of the Upper Silurian, 119; of the Devonian, 141; of the Carboniferous, 172-174; of the Permian, 197; of the Upper Greensand, 266.
Rupelian Clay, 307.