Palæolithic fauna and flora, 270-274 Palæolithic man, 268, 272-274 Palæolithic period, 267-274 Palæontological break, 61 Palæo-physiography, 120 Paradoxides fauna, 152, 160, 161 Peat deposits, 275, 276 Pebble beds of Bunter, 218 Pebidian rocks, 140 Pengelly, W., 270 Pennant stage, 192 Pennine system of folds, 203 Penrith sandstone, 75, 210, 211 Period, definition of, 60 Permanence of ocean basins, 278-285 Permian fauna and flora, 214-216 Permian system, 209-217 Permo-carboniferous fauna and flora, 207, 208 Permo-carboniferous glacial deposits, 206 Permo-carboniferous period, 205-208 Phillips, J., 10, 11, 201 Physical break, 60 Pickwell Down sandstone, 183 Pilton beds, 183 Plaisancean series, 256 Planes of lamination, 27 Planes of stratification, 27 Pleistocene fauna and flora, 265, 266 Pleistocene period, 260-266 Pliocene fauna and flora, 259 Pliocene period, 256-259 Portland oolites, 226 Portlandian series, 226, 232 Prado, C. de, 161 Precambrian rocks, 132; mode of formation of, 146 Preller, C. S. du R., 264 Prestwich, Sir J., 19, 130, 279 Productus limestones, 205, 206, 214 Protolenus fauna, 160 Pseudo-stromatism, 76 Purbeckian series, 226, 232 Pyroclastic rocks, 24 Quader sandstone, 240 Ramsay, Sir A. C., 130, 153, 163, 188 Reading beds, 244 Recurrences, 292 Red crag, 256, 257 Reid, C., 45, 257, 264, 268, 271 Renard, A., 30 Reversed fault, 34 Rhætic beds, 218 Rhiwlas limestone, 167 Richthofen, Baron von, 267, 268 Ridley, H. N., 271 River drift man, 268 Rotherham red rock, 202 Rothliegende, 209 Rouelle, 13 St Bees sandstone, 210 St Erth beds, 257 Salopian beds, 175 Salter, J. W., 161, 162, 186 Scarbro' limestone, 230, 231 Schists, crystalline, 76, 77, 133, 147 Scilla, A., 13 Screes, 101 Scrope, G. P., 76 Sections, geological, 84; use of, 88 Sedimentary rocks, 23 Sedgwick, A., 16, 19, 20, 153, 174 Senonian series, 236 Series, definition of, 60 Seward, A. C., 113, 208 Sigmoidal structure, 33 Siliceous rocks, 29 Silurian faunas, 179, 180 Silurian system, 174-182 Simulation of structures, 72 Sinemurian series, 227, 229 Smith, W., 8, 12-18, 57, 85 Soil, 100 Solenhofen slate, 234 Sollas, W. J., 288 Solva beds, 152, 154, 156, 161 Speckled sandstone, 205, 206 Speeton series, 238 Spencer, H., 50 Spirorbis limestone, 201 Stages, definition of, 60 Steppe period, 260, 267-274 Stonesfield slate, 231 Strachey, J., 10 Strahan, A., 239, 264 Strata, 27; classification of, 58, 125 Stratification, 26 Stratified rocks, 23; composition of, 28; origin of, 29; classification of, 28, 125; symbols to represent, 90 Stratigraphical geology, aim of, 1; W. Smith, founder of, 8, 12-18 Suess, E., 110, 123, 207, 284 Superposition, law of, 31 Surveying, geological, 84 Systems, definition of, 60