The Student's Elements of Geology

by Sir Charles Lyell

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]

TABLE of Botanical Nomenclature, [303]
—— of St. Cassian fossil mollusca, [377]
—— of Cretaceous formations, [283]
—— of Devonian series in Devon, [449]
—— of divisions of Hastings Sand, [316]
—— of English and French Eocene strata, [252]
—— of ages of fossil vertebrata, [464]
—— of Neocomian strata, [308]
—— of mammalia older than Paris gypsum, [329]
—— of marine testacea in the Crag, [202]
—— of Oolitic strata, [321]
—— of volcanic minerals, [499]
—— of Silurian strata of United States, [478]
—— of Silurian rocks, [458]
—— of Triassic strata, [375]
—— of Cambrian strata, [482]
—— of Permian of north of England, [386]
—— of Welsh coal-measures, [394]
—— of thicknesses of Carboniferous limestone, [395]
——, general, of fossiliferous strata, [131]
Table Mountain, granite veins in clay-slate of, [560]
Tails of homocercal and heterocercal fish, [389]
Talcose granite, [557]
—— gneiss, [578]
Tarannon shales, [468]
Tartaret cone, and lava of, [527], [542]
Tate, Mr., on St Cassian fossils, [377]
Tealby series, Middle Neocomian, [312]
Teeth of extinct mammalia, [163], [164]
Tellina balthica (T. solidula), [190]
—— calcarea (T. proxima), [177]
—— obliqua, Crag, [194]
Temnechinus excavatus, [200]
Temnopleurus excavatus, [200]
Tentaculites annulatus, Silurian, [489]
Terebellum fusiforme, Barton, [259]
—— sopita, Barton, [259]
Terebratula affinis, Aymestry, [462]
—— biplicata, White Chalk, [294]
—— carnea, White Chalk, [294]
—— digona, Bradford clay, [345]
—— fimbria, Inferior Oolite, [350]
—— hastata, Mountain Limestone, [434]
—— sella, Neocomian, [310]
—— Wilsoni, Aymestry, [462]
Terebratulina striata, White Chalk, [294]
Terebrirostra lyra, Chloritic Sand, [300]
Teredo navalis, boring wood, [50]
Tertiary formations, classification of, [137], [143]
—— strata, subdivisions of, [143]
——, term defined, [123]
Testacea. See Shells.
Thallogens, [303]
Thamnastræa, Coral Rag, [339]
Thanet sands, [269]
Theca operculata, Tremadoc beds, [483]
Thecodontosaurus, tooth of, [374]
Thecodus parvidens, Ludlow, [460]
Thecosmilia annularis, Coral Rag, [339]
Thirria, M., on Nerinæan limestone, [340]
Thompson, Dr., on Nummulites of Thibet, [277]
Thomson, Wyville, on Atlantic mud, [288]
——, on sponges in chalk mud, [292]
Thuringia, monitor of, [390], [463]
Thurmann, M., on Bernese Jura Oolite, [344]
——, on structure of the Jura, [83]
Thylacotherium Prevostii, Stonesfield, [347]
Tile-stones of the Upper Ludlow, [459]
Tilgate forest, fossil Iguanodon in, [315]
Till described, [166]
——, mammoth in Scotch, [175]
—— of North America, [182]
Tin veins, age of, in Cornwall, [615]
Titanoferrite, [500]
Torell, Dr., on ice-action in Greenland, [172]
——, on Swedish Cambrian fossils, [489]
Touraine, faluns of, [211]
Tourmaline, [500]
Trachytic rocks, [505]
—— tuff, [506]
—— porphyry, [506]
—— lava, age of, [523]
Trap, term defined, [498]
—— dike, intercepting strata, [518]
—— dikes, [513-17]
——, intrusion of, between strata, [517]
—— rocks, ages of, [524-50]
—— rocks passing into granite, [559]
—— tuff described, [508]
Trappean rocks, nomenclature of, [497]
—— rocks, their relation to active volcanoes, [517]
Trass of Lower Eifel, [535]
Travertin, how deposited, [60]
——, inférieur of Paris basin, [273]
Tree ferns, living, [422]
Trees erect in coal, Nova Scotia, [411]
Tremadoc slates and their fossils, [482]
Tremolite, [499], [502]
Trenton limestone, fossils of the, [479]
Trezza, volcanic rocks of, [529]
Trias, beds of passage between Lias and, [366]
—— of England, [369-74]
—— of Germany, [375]
——, Saurians of the, [370]
—— of the United States, [381]
Triassic mammifer, North Carolina, [383]
Triclinic feldspars, [501]
Tridymite, crystallised silica, [500]
Trigonellites latus, Kimmeridge clay, [336]
Trigonia caudata, Neocomian, [310]
—— gibbosa, Portland stone, [335]
Trigonocarpum ovatum, and T. olivæforme, Coal, [429]
Trigonotreta undulata, Permian, [388]
Trilobites of Bala and Caradoc beds, [471]
——, metamorphosis of, [471], [488]
—— of primordial zone, [487]
Triloculina inflata, Eocene, [275]
Trimmer, Mr., on contorted strata, [179]
——, on shells of Moel Tryfaen, [186]
Trinucleus concentricus, T. Caractaci, [472]
Trionyx, carapace of, Bembridge, [253]
Tripoli composed of diatomaceæ, [51]
Trochoceras giganteus, Ludlow, [463]
Trophon antiquum (Fusus contrarius), [196]
—— clathratum, Scotch drift, [176]
Tuff defined, [30]
——, shelly, of the Grand Canary, [538]
——, trappean, of Llandeilo rocks, [473]
——, shelly, of Gergovia, [542]
Tupaia Tana, recent, [347]
Turner, Dr., on chemical decomposition, [68]
Turrilites costatus, Chalk, [299]
Turritella multisulcata, Bracklesham, [262]
Tuscany, mineral springs of, [604]
Tylor, Mr., on amount of subaërial denudation, [114]
Tyndall, Dr., on slaty cleavage, [594]
Tynedale fault, [90]
Tynemouth cliff, brecciated limestone of, [387]
Typhis pungens, Barton clay, [259]

UNCITES Gryphus, Devonian, [452]
Unconformability of strata, [94], [138]
Underlying, term applied to plutonic rocks, [34]
Unger on American forms in Swiss Miocene flora, [223], [239]
—— on Miocene plants of Croatia, [243]
Ungulite, or Obolus grit of Russia, [477]
Unio littoralis, [54]
—— Valdensis, Hastings Sands, [317]
United States, Cambrian of the, [489]
——, Cretaceous rocks of, [307]
——, Devonian of, [455]
——, Eocene strata in the, [278]
——, footprints in Carboniferous of, [407]
——, Lower Miocene of, [248]
——, older Pliocene and Miocene formations of, [227]
——, Silurian strata of, [478]
——, Trias of the, [381]
Upheaval of land more than counteracted by subsidence, [116]
——, power of denudation to counteract, [105], [115]
Upper Greensand, or Chloritic series, [298]
Upsala, erratics on modern marine drift near, [174]
Ural Mountains, auriferous alluvium of, [616]
Uralite, [499]
Ursus spelæus, tooth of, [165]
Urville, Captain de, on size of icebergs, [172]

VAL D’ARNO, Newer Pliocene of, [207]
Valleys, origin of, [102]
Valorsine, granite veins in talcose gneiss in, [599]
Valvata piscinalis, [55]
Vanessa Pluto, Lower Miocene, Croatia, [243]
Vegetation of the Coal, [420]
—— of the Devonian of America, [455]
——. See Plants.
Veins, chemical deposits in, [612]
——, granite rocks altered by, [559]
——, different kinds of minerals, [605]
——. See Mineral veins.
Vein-stones, [610]
Venericardia planicosta, [260]
Venetz, M., on Alpine glaciers, [170]
Ventriculites radiatus, Chalk, [292]
Verneuil, M. de, on Russian Silurian, [462]
——, on Permian flora, [392]
Vertebrata, progress of discovery of fossil, [464]
Vertical strata, [73]
Vesuvius, Recent and Post-pliocene volcanic rocks of, [525]
——, basaltic lavas of, [508]
——, tufaceous strata of, [522]
——, dikes of, [527]
Vicarya Lujani, Punfield, [319]
Vicentin, columnar basalt of the, [511]
Vienna Basin, Upper Miocene beds of, [224]
Vine in Upper Miocene beds at Œningen, [221]
Virginia, eighty miles of fault in, [92]
——, coal-field of, [382]
Virlet, M, on corrosion of rocks near Corinth, [586]
——, on Cretaceous traps of Greece, [544]
——, on fossils in veins, [608]
——, on volcanic rocks of the Morea, [544]
Volcanic ash or tuff, [508]
—— breccia, [509]
—— dikes, [513-16]
—— force and denudation opposing powers, [117]
—— mountains, structure and origin of, [494]
Volcanic rocks defined, [29]
——, mineral composition of, [498]
——, Recent and Post-pliocene, [524]
——, Pliocene, [529]
——, Miocene, [536-43]
——, Eocene, [543]
——, Cretaceous and Liassic, [544], [545]
——, New Red, Permian and Carboniferous, [545]
——, Old Red Sandstone, [547]
——, Silurian, Cambrian and Laurentian, [548], [549]
—— of Auvergne, [540]
——, columnar and globular, structure of, [510]
—— of Grand Canary, [528]
—— of Silurian age, [477]
——, special forms of structure of, [506]
——, tests of age of, [520-4]
Volcanoes, extinct, [30]
—— of Auvergne, [495]
Voltzia heterophylla, Bunter, [380]
Voluta ambigua, Barton clay, [259]
—— athleta, Barton, [259]
—— Lamberti, coralline and Red Crag, [196]
—— Lamberti, faluns, [214]
—— nodosa, London clay, [266]
—— Selseïensis, Bracklesham, [262]
Von Buch, Leopold, on “elevation craters,” [496]
——, on Silurian plutonic rocks, [572]

WACKE described, [508]
Wagner, M., on Miocene of Greece, [226]
Walchia piniformis, Permian, [392]
Wales and England, glaciation of, [180]
Wallich, Dr., on Atlantic mud, [287]
Water, denuding power of running, [98], [115]
——, action of, in metamorphism, [584]
Watt, Gregory, on fusion of rock, [584]
Weald clay and its fossils, [317]
Wealden area, thickness of the, [319]
—— formation, [313]
—— flora, [320]
Webster, Mr. T., on Tertiary strata, [141]
Wellington Valley caves, [158]
Wenlock formation, fossils of the, [465-8]
—— limestone, [465]
—— shale, [467]
Werner on mineral veins in Saxony, [609]
—— on isomorphism, [502]
Westwood, Mr., on Lias beetles, [363]
Wexford, veins of copper at, [615]
Whitaker, Mr., on subaërial origin of escarpments, [104]
White or coralline crag, [197]
—— sand of Alum Bay, [38]
Whymper, Mr., on Arctic Miocene plants, [240]
Williams, Mr., on Cornish lodes, [607]
Williamson, Professor, on Conifers of the Coal, [428]
——, on structure of calamite, [425]
Wind, denuding action of the, [97]
Wood, Mr. Searles, on Bridlington shells, [190]
——, on Chillesford and Aldeby beds, [192]
——, on shells of the Crags, [194], [195], [199]
——, on shells of Crag and faluns compared, [213]
——, on fish of Headon series, [255]
——, table of marine testacea of the Crag, [202]
——, on thickness of coralline crag, [198]
Woodward, Dr., on St. Cassian fossils, [377]
Woodward, Mr. H., on Pterygotus, [447]
Woolhope beds, [467]
Woolwich and Reading series, [267]
Wright, Dr., on Barton shells, [258]
——, on zones of the Lias, [353]
Wunsch, Mr. E. A., on trees in volcanic ash, [546]
Wyville Thomson. See Thomson.

XIPHODON gracile, Paris basin, [271]
Xylobius Sigillariæ, Nova Scotia coal, [415]

YOREDALE beds, thickness of the, [395]
Yorkshire, Oolite of, [349]
Young, Mr., on seeds washed out of mammoth tusks, [176]

ZECHSTEIN of Germany, [392]
Zeolites, secondary volcanic minerals, [500]
Zeuglodon cetoides, Eocene, United States, [280]
Zircon-syenite, [558]
Zoantharia rugosa and Z. aporosa, [431]
Zones of the Lias, [353]
Zonites priscus, Coal, [415]
Zoological provinces, great extent of, [127]
Zoophytes, fossil, [48]
——. See Corals, Bryozoa, etc.
Zurich, lake-dwellings in Lake of, [148]