PAGHAM, erratic block at, 182
Palæaster asperimus, 472
Palæchinus gigas, Mountain Limestone, 43
Palæocoma tenuibrachiata, Lias, 357
Palæoniscus, Permian fish, 389
—— comptus, P. elegans, P. glaphyrus, 390
Palæotherium magnum, 254
Palæophis typhoeus, Bracklesham, 261
Palæozoic or Paleozoic, term defined, 123
—— Plutonic rocks, 572
—— rocks, 458
—— type of corals, 431
Palagonia, dikes of lava in, 531
Paleolithic era, 147, 149
——, alluvial deposits of, 150
Palm in Swiss Miocene, 237
Palma, volcanic crater of, 497
Paludina lenta, Hempstead beds, 55
—— orbicularis, Bembridge, 253
Paradoxides Bohemicus, 488
—— Davidis, Lower Cambrian, 485
Parallelism of folded strata for long distances, 93
Paris basin, Tertiary group first studied in, 141
——, Tertiaries of the, 270
Parka decipiens, “Old Red,” 448
Parkfield Colliery, ground-plan of, 400
Patagonia, strata of, rich in soda, 587
Patella rugosa, Great Oolite, 345
Paterson, Dr., on angiosperm of the Coal, 429
Peach, Mr. C, cited, 601
——, Pteraspis, found by, 443
Pearlstone, 505
Pebbles in mineral veins, 608
—— in chalk, 292
Pecopteris elliptica, Coal, 421
Pecten Beaveri, White Chalk, 294
—— cinctus, Neocomian, 312
—— islandicus, Scotch Drift, 176
—— jacobæus, in tertiary of Sicily, 206
—— quinque-costatus, 300
—— Valoniensis, Rhætic beds, 366
Pegmatite, 553
Penarth beds, 366
Pengelly, Mr., on Bovey Tracey lignite, 246
——, on flint-knives of Brixham Cave, 157
Pentacrinus Briareus, Lias, 357
Pentamerus Knightii, Aymestry, 461
—— oblongus, and P. lirata, 469
Pentland Hills, volcanic rocks of the, 548
Perigord cave, carving of mammoth in, 150
Permanence of continents and oceans, 117
Permian Flora, 392
—— of Germany, 393
—— strata, thickness of, in north of England, 386
——, Upper and Middle, 386, 387
——, Lower, 390
Perna Mulleti, Neocomian, 310
Petherwyn, Devonian fossils of, 450
Petrifaction, process of, 67
Petrophiloides Richardsoni, Sheppey, 25
Pahcops caudatus, Silurian, 467
—— latifrons, Devonian, 450
Phascolotherium Bucklandi, 348
Phasianella Heddingtonensis, and cast, 66
Phillippi, on tertiary shells of Sicily, 205
Phillips, Professor, on fossils distorted by cleavage, 592
——, on ninety fathom dike, 90
——, on Wenlock limestone and shale, 465, 467
——, on Yoredale series, 395
Phillips, Mr. J. Arthur, on origin of gold of California, 617
Phlebopteris contigua, Inferior Oolite, 350
Phlogopite, 499, 501
Pholadomya fidicula, Inferior Oolite, 350
Phonolite, 506
Phorus extensus, London Clay, 266
Phragmoceras ventricosum, Silurian, 463
Physa Bristovii, Middle Purbeck, 325
—— columnaris, 55
—— hypnorum, 55
Piedmont, absence of lakes in, 186
Pile dwellings of Switzerland, 148
Pilton, group of, Devon, 449
Pinnularia in Atlantic mud, 288
Pinus sylvestris in peat, 147
Pisolitic limestone of France, 285
Pitchstone, 505
Placodus gigas, Muschelkalk, 380
Placoids, rare in Old Red Sandstone, 443
Plagiaulax Becklesii, jaw and molar of, 327
Plagioclastic feldspars, 501
Plagiostoma giganteum, Lias, 354
—— Hoperi, Chalk, 300
Planorbis discus, Bembridge, 253
—— euomphalus, 55, 255
Plants of Bovey Tracey, Miocene, 247
——, fossil fresh-water, 57
—— of the Coal, 420
—— of the Lias, 364
—— of the Swiss Upper Miocene, 219
Plas Newydd, rock altered by dike near, 515
Plastic Clay, Eocene, 267
Platanus aceroides, Miocene, 221
Platystoma Suessii, Hallstadt, 377
Playfair, on amount of subaërial denudation, 114
—— on faults, 87
Plectrodus mirabilis, Ludlow, 460
Plesiosaurus dolichodeirus, Lias, 361
Pleurotoma attenuata, Bracklesham, 262
—— exorta, Eocene, 57
Pleurotomaria anglica, and cast, 66
—— carinata (flammigera), 434
—— granulata, Inferior Oolite, 351
—— ornata, Inferior Oolite, 351
Plieninger, Professor, on Triassic mammifer, 368
Pliocene glacial formations, 189-92
—— Period, 189
—— plutonic rocks, 565
—— strata of Sicily, 204
——, term defined, 143
—— volcanic rocks, 529
Plombières, alkaline waters of, 585
Plumbago of Massachusetts, 583
Plutonic and sedimentary formations, diagram of, 567
——, origin of the term, 551
—— rocks, Mesozoic, 570
——, Recent and Pliocene, 565
——, Miocene and Eocene, 568
——, uncertain tests of age of, 564
—— defined, 31
Podocarya Bucklandi, Oolite, 348
Polypterus of the Nile, 444
Polyzoa and Bryozoa, terms explained, 197
Pomel, M., on fossil mammalia of the Limagne, 235
Ponza Islands, globiform pitchstone of, 512
Porites pyriformis, Devonian, 451
Porphyritic granite, 556
Porphyry, 506
Portland, Cycads in dirt-bed of, 331
—— oolite and sand, 334
“Portland screw,” a cast of a shell, 335
Porto Santo, marine shells in volcanic tuff of, 536
Post-pliocene period, climate of the, 161
—— mammalia, teeth of, 163
——, term defined, 145
—— lakes of Switzerland, 185
—— volcanic rocks, 524
Potamides cinctus, 56
Pothocites Grantonii, coal-measures, 429
Potsdam Sandstone, 480, 489
Pot-stones in the Chalk, 290
Pottsville, coal seams of, 400
Powrie, Mr., on Cephalaspis beds, 446
——, on Parka decipiens, 448
Pratt, Mr., on Eocene Isle of Wight mammalia, 254
Predazzo, altered rocks at, 571
Pressure, solidifying rocks, 65
Prestwich, Mr., on age of Sables inferieurs, 276
——, on Chillesford beds, 192
——, on Coalbrook Dale insects, 405
——, on Eocene strata, 267, 269
——, on faults in coal-measure of Coalbrook Dale, 88
——, on shells of London clay, 264
——, on thickness of Coralline Crag, 198
Prévost, M. Constant, on Paris basin, 270
Primary Limestone, 579
—— rocks, 458
——, term defined, 123
“Primordial Zone” of Bohemia, 481, 482
Productus horridus, Permian, 388
—— semireticulatus (antiquatus), 434
Progressive development indicated by low grade of early mammals, 384
Proteaceæ of Aix-la-Chapelle flora, 304
—— of Lower Molasse, Switzerland, 237
—— of Œningen beds, 221
Protogine, 578
Protosaurus of Thuringia, 390, 464
Protrusion of solid granite, 574
Provinces of animals and plants, 126
Psammodus porosus, 437
Pseudocrinites bifasciatus, Silurian, 466
Psilophyton princeps, Devonian, 455
Pteraspis in Lower Ludlow shale, 463
Pterichthys, Old Red Sandstone, 445
Pterodactyl of Kentish chalk, 297
Pterodactylus anglicus, Old Red, 447
—— crassirostris, Solenhofen, 337
Ptychodus decurrens, White Chalk, 297
Pudding-stone or conglomerate, 36
——, formation of, 62
Pumice, 508
Punfield beds, brackish and marine, 318
Pupa muscorum, 155
—— tridens, Loess, 56
—— vetusta, Coal, 415
Purbeck beds, Upper, Middle, and Lower, 323, 324, 336
——, fossil mammalia of the Middle, 325
—— marble, 324
——, subdivisions of the, 333
Purity of coal, cause of, 402
Purpura tetragona, Red Crag, 196
Purpuroidea nodulata, Great Oolite, 345
Puy de Côme, cone and lava-current of, 528
—— de Tartaret, lava-current and cone of, 527, 542
—— de Pariou, crater of the, 529
Puzzuoli, elevation of land at, 525
Pygopterus mandibularis, Permian, 390
Pyrenees, chalk altered by granite in the, 570
——, curved strata in, 86
——, lamination of clay-slate in, 596
Pyroxene group of minerals, 499, 502
Pyrula reticulata, Crag, 200

QUADER-SANDSTEIN, Cretaceous age of the, 293
Quadrumana of Gers, 215
Quadrupeds, extinct, in Paleolithic gravels, 152
Quartz, specific gravity of, 499, 500, 555
Quartzite or Quartz Rock, 579
Queenaig, unconformable Palæozoic strata at, 112
Quenstedt on zones of Lias, 353

RADABOJ Miocene, brown coal of, 242
Radiolites foliaceus, White Chalk, 306
—— Mortoni, White Chalk, 295
—— radiosa, White Chalk, 306
Radnorshire, stratified trap in, 549
Rain-prints with worm tracks in Coal, 416
——, carboniferous, 416
Ramsay, Professor, on break between Upper and Lower Cretaceous, 301
——, on breccias in Permian, 391
——, on escarpments, 104
——, on denudation, 98
——, on ice-erosion of lake-basins, 184
——, on Lingula Flags, 484
——, on position of Tremadoc beds, 483
——, on Silurian metamorphic rocks, 602
——, on submergence in glacial period, 181
——, on thickness of the Lower Trias, 372
——, on thickness of Llandeilo beds, 475
——, on thickness of the Bala beds, 473
——, on volcanic tuffs of Snowdon, 549
——, on zones of the Lias, 353
Rastrites peregrinus, Llandeilo Flags, 473
Rath, Von, on Tridymite, 500
Recent Period defined, 145
—— volcanic rocks, 524
Record, imperfection of, in the earth’s crust, 138
Red Crag, older Pliocene, 194
—— Sandstone, Origin of, 374
—— Sea and Mediterranean, distinct species in, 127
Redruth, Cornwall, section of veins in mine, 607
Reindeer Period in South of France, 149
Relistran mine, pebbles in tin of, 609
Reptiles of the Coal, 406, 413
Reptiles of the Lias, 360
Retepora flustracea, Permian, 388
Rhætic beds between Lias and Trias, 366
Rhine, fresh-water strata of the, 53
——, loess of the, 154
Rhinoceros in drift of Abbeville, 153
—— leptorhinus (megarhinus), molar of, 164
—— tichorhinus, molar of, 164
Rhode Island, metamorphic rocks of, 583
Rhynchonella navicula, Ludlow, 460
—— octoplicata, White Chalk, 294
—— spinosa, Inferior Oolite, 350
—— Wilsoni, Aymestry, 462
Richmond, Virginia, Triassic coal-field of, 382
Rigi and Speer, Lower Miocene of the, 235
Rimula clathrata, Great Oolite, 345
Rink, Mr., on Greenland land-ice, 171
Ripple-marked sandstone, how formed, 46
Rise and fall of land, 146
Rissoa Chastelii, Hempstead beds, 245
Rivers, denuding powers of, 101, 114
Roches moutonnees described, 169
Rock, term defined, 26
Rocks altered by volcanic dikes, 514
—— altered by subterranean gases, 586
——, analysis of minerals in, 499
——, aqueous or stratified, 27
——, classification of, 121
——, great thickness of palæozoic, 110
——, glacial scorings on, 169
——, metamorphic, age of, 597
——, plutonic age of, 564
——, volcanic, age of, 520
——, trappean, 497
——, metamorphic, defined, 32
——, four classes of contemporaneous, 33
——, plutonic, defined, 31
——, tests of age of, 123, 125, 520, 564, 597
——, four contemporaneous classes of, 122
——, underlying, not always the oldest, 122
——, volcanic, defined, 29
Rock-salt of Trias, 371
——, origin of, 374
Rogers, Mr. H. D., on blending of coal-seams, 400
——, on Virginian fault, 92
Rose, Gustavus, on isomorphism, 502
——, on Fifeshire dike, 546
——, on quartz in granite, 555
Rosso antico, red porphyry of Egypt, 506
Rostellaria (Hippocrenes) ampla, London Clay, 266
Roth, M., on Miocene of Greece, 226
Runn of Cutch, salt of, 375
Rupelian beds of Dumont, 241, 242
Russia, glaciation of, 174
——, Devonian of, 454
——, Silurian strata of, 478

SAARBRUCK, reptiles in coal-field of, 406
Sabal major, Lower Miocene, 237
Sables de Bracheux, 276
—— moyens, Paris basin, 273
Sahlite, 502
St. Abb’s Head, curved strata of, 76
——, unconformable stratification at, 94
St. Andrews, carboniferous trap-rocks of, 545
St. Cassian, fossil mollusca of, 377
—— and Hallstadt beds, 376
St. David’s, Menevian beds of, 485
St. Mary’s, shells of, 539
Salt, rock, origin of, 372
Salter, Mr., on fossils of Arenig group, 476
——, on Menevian beds, 485
——, on Tremadoc fossils, 483
Sandberger, Dr. F., on Mayence basin, 242
Sandstone, New Red, 369
——, Old Red, 439
—— slab with cracks, 317
——, slab of ripple-marked, 45
—— slab with footprints, 408
Sao hirsuta, 488
Saurians of the Lias, 361
——, sudden destruction of, 362
Saurichthys apicalis, Rhætic Beds, 367
Saussure, on vertical conglomerates, 73
Saxicava rugosa, Scotch drift, 176
Saxony, beds of minerals in, 609
Scandinavia, glaciation of, 174
Scaphites æqualis, Chloritic marl, 299
Scapolite, 506
Scheerer on action of water in metamorphism, 585
Schist, mica, 578
——, argillaceous, 579
——, hornblende, 578
Schizodus Schlotheimi, Permian, 387
—— truncatus, Permian, 387
Schmerling, Dr., on Liége caverns, 157
Schorl-rock, and schorly granite, 557
Schwab, M., on Celtic coins in lake-dwellings, 149
Scoliostoma, St. Cassian, 377
Scoresby, on Arctic icebergs, 172
Scoriaceous lava, 507
Scoriæ, 508
Scotland, “Fundamental gneiss” of, 493
——, Old Red Sandstone of, 440
——, glaciation of, 175
Screws, fossil, internal casts of shells, 66
Scrope, Mr., on Isle of Ponza, globiform pitchstone, 512
——, on minerals in lava, 524
——, on water in lava, 555
Scudder, Mr., on Devonian insects of Canada, 457
Sea, apparent fall of, caused by rise of land, 70
——, denuding power of the, 105
——, deep soundings in, 287
——, mean depth of the, 118
—— cliffs, inland, 103
Secondary and Tertiary, gap between the, 281
——, term defined, 123
Section of Auvergne alluvium, 100
—— of carboniferous rocks, Lancashire, 85
—— of chalk and greensand, 287
—— of crags near Woodbridge, Suffolk, 198
—— of cross-stratification, 42-44
—— of curved strata of the Jura, 82
—— of dirt-bed in Isle of Portland, 332
—— of Forfarshire, showing curved strata, 74
—— of fossil tree, showing texture, 67
—— of folded and denuded carboniferous beds, Nova Scotia, 418
—— of the Oolitic strata, 322
—— of Recent and Post-pliocene alluvial deposits, 151
—— showing creeps in coal-mines, 79
—— of slaty cleavage, 589
—— showing valleys of denudation, 98
—— showing the Weald formation, 313
—— of strata thinning out, 41
—— of superimposed groups at Dundry Hill, 130
—— of unconformable strata near Mons, 95
Sections illustrating faults, 88, 90, 91
Sedgwick, Professor, on the Cambrian Group, 481, 482, 486
——, on classification of Arenig group, 476
——, on Devonian series, 439, 449
——, on position of the May-Hill beds, 568
——, on protrusion of solid granite, 574
——, on slaty cleavage, 588, 591
——, on garnet in altered rock, 515
——, on concretionary structure, 63
Sediment, accumulation of, causing a shifting of the subterranean, 117
isothermals. Sedimentary beds of the Carboniferous, 396
Selsea Bill, erratics at, 182
Senarmont on action of water in metamorphism, 585
Sequoia Langsdorfii, 238
“Seraphim,” head of Pterygotus anglicus, 446
Serapis, marine littoral deposits of, 146
Serpentine, 578
Serpulæ attached to Gryphæa, 48
—— attached to Spatangus, 49
—— attached to Apiocrinus, 343
Shale defined, 36
—— of the Lower Ludlow, 461
Sharpe, Mr. D., on American Silurian fossils, 479
——, on fossils distorted by cleavage, 592
Shell-mounds of Denmark, 146
Shells, Arctic, in Scotch drift, 177
——, derivative, in the Crag, 195-203
——, marine, found at great heights above the sea, 29
——, proportion of living, in the Crags, 194, 195, 199
——, value of, in classification, 142
——, fossil, of Virginia, 228
—— of the London clay, 266
—— of the mountain limestone, 433
—— of the Barton clay, 258
—— of the Oolite, 335, 345, 350
——, marine, of Moel Tryfaen, 180
Sheppey, fauna and flora of, 264
——, Eocene fish of, 267
Sherringham, erratic block at, 191
Shetland, granite of, 558
——, hornblende-schist of, 583
Sicily, fauna and flora of, older than the country itself, 207
——, newer Pliocene strata of, 204
——, subterranean igneous action in, 569
——, undulating gypseous marls of, 86
——, volcanic dikes of, 531
Sidlaw Hills, trap of, 548
Sigillaria in coal-measures, 380, 411, 425
Sigillaria lævigata, coal-measures, 426
Siliceous limestone defined, 37
Silurian, derivation of the name, 458
——, granite of Norway, 573
——, metamorphic, of North Highlands, 601
—— rocks, classification of, 458
—— strata of the continent of Europe, 477
—— strata of United States, 478
—— volcanic rocks, 548
Siphonotreta unguiculata, obolus grits, 478
Siwâlik Hills, fresh-water deposits of, 226
Skaptar Jokul, flow of lava from, 523
Skye, hypersthene rocks of, 491
——, Isle of, Miocene syenite of the, 568
——, trap dike in, 514
Slaty cleavage, 588
Slicken-sides, in opposite walls of veins, 608
——, term defined, 87
Smilax sagittifera, Œningen, 222
Smith, Mr. W., on White Lias bed, 366
Snowdon, volcanic tuffs of, 549
Soissonnais sands, 275
Solenastræa cellulosa, Brockenhurst, 257
Solenhofen stone, fossils in the, 337
Solfatara, decomposition of rocks in the, 586
Somma, cone and dikes of, 526
Sopwith, Mr. T., models of outcrop of strata, 85
Sorby, Mr., on action of water in metamorphism, 585
——, on glass cavities in quartz, 555
——, on mechanical theory of cleavage, 592
——, on ripple-marks in mica schist, 596
South Joggins, section of cliffs at, 410
Spalacotherium, Purbeck, 346
Spatangus radiatus, Chalk, 284
—— with serpula attached, 49
Species, gradual change of, 139
—— older than the land they inhabit, 207
——, similarity of conditions causing reappearance of, 311
Specific gravity of basalt and trachyte, 504
Speer and Rigi, Lower Miocene of the, 235
Speeton Clay, 311
Sphærexochus mirus, Silurian, 467
Sphærulites agariciformis, White Chalk, 306
—— of volcanic minerals, 499
Sphenophyllum erosum, Coal, 425
Sphenopteris gracilis, Hastings sands, 318
Spheroidal concretions in limestone, 64
Spicula of sponge, Atlantic mud, 288
Spirifera disjuncta, Devonian, 450
—— alata, Permian, 388
—— mucronata, 454
—— trigonalis, and S. glabra, 434
Spiriferina Walcotti, Lias, 355
Spirolina stenostoma, Eocene, 275
Spirorbis carbonarius, coal-measures, 405
Spondylus spinosus, White Chalk, 294
Sponge in flint from White Chalk, 296
Sponges, vitreous, in the chalk, 291
Springs, mineral of Auvergne, 604
Staffa, age of columnar basalt of, 539
Stalactite, origin of, explained, 156
Starfish in Silurian strata, 472
Stations of species affecting distribution of fossils, 354
Stauria astræiformis, 431
Stereognathus of Stonesfield, 348
Sternberg, Count, on insects in coal, 495
Stigmaria attached to trunk of Sigillaria, 427
—— in coal-measures, 398, 411, 426
—— ficoides and surface showing tubercles, Coal, 427
Stilbite, 500
Stiper-Stones or Arenig Group, 475
Stockwerk, assemblage of veins, 605
Stonesfield slate, mammalia of the, 345
Strata, term defined, alternations of fresh-water, and shallow and deep, 27
sea. ——, alternations of marine and fresh-water, 108
——, curved, inclined, and vertical, 73
——, apparent horizontality of inclined, 81
——, contorted in drift, 178
——, contortion of, in Cyclopean Isles, 530
——, general table of fossiliferous, 131
——, horizontality of, 40
——, origin of metamorphic, 83
——, overlapping, 95
—— repeated by being doubled back, 87
——, slow growth of, attested by fossils, 47-50
—— of organic origin, 51
——, tests of age of, 123
——, unconformability of, 94, 138
——, vast thickness of, not forming high mountains, 109-13
Stratification, diagonal or cross, 42, 44
——, different forms described, 39
—— of metamorphic rocks considered, 580
Stratified rocks, composition of, 35
Striæ, production of, 168
Strickland, Mr., on thickness of the Trias, 369
Stricklandinia lirata, 469
Strike, term explained, 80
Stringocephalus Burtini, 452
Stromboli, lava of, 566
Strophomena depressa, Wenlock, 466
—— grandis, 471
Studer, Mr., on gneiss of the Jungfrau, 599
subaërial denudation, average annual amount of, 113
Subapennine beds, proportion of recent species in, 143
—— strata, older Pliocene, 208
Submarine denudation, 105
Subsidence of land must preponderate over upheaval, 116
Succinea amphibia, 55
—— elongata, 155
Suess, M., on fossils of St. Cassian beds, 376, 377
——, on Vienna basin, 225
Suffolk, Crag of, 195
“Sunk country,” New Madrid, 402
Superga, Lower Miocene of the, 244
Superior, Lake, marl in, 63
Superposition of deposits, a test of age, 124
—— a test of age of volcanic rocks, 521
Sutherlandshire, unconformable Palæozoic strata in, 112
Swanage, fossil mammalia found at, 326
Sweden, Cambrian of, 489
——, slow rise of land in, 72
——, small thickness of Silurian strata in, 477
Switzerland, lake-dwellings of, 148
——, Lower Molasse of, 235
——, Middle or Marine Molasse of, 223
——, Upper Miocene of, at Œningen, 215
Sydney coal-field, rain-prints in, 416
Syenite, composition of, 552, 557
——, how far connected with trap-rocks, 558
Syenitic granite, 557
Symonds, Rev. W. S., on Moel Tryfaen shells, 180
Synclinal and anticlinal curves, 74, 85