Dalmatia, 170 Darwin's theory of coral reefs, 191 Dead Sea, 221, 279 Death Gulch, 264 Deep-sea deposits, 187 Deer, 413 Deflation, 152 Deformation, 279 Delaware River, 197, 403 Deltas, 108, 111, 197 of Ganges, 109 of Indus, 110 of Mississippi, 109, 197 Denudation, 57 Denver, 398 Desert, 15, 55 Devitrification, 257 Devonian period, 316, 341 Dicotyls, 377, 404 Digitigrade, 406 Dikes, 244, 265 Dinosaurs, 385 Dinothere, 410 Diorite, 274 Dip, 202 Dip fault, 225 Diplodocus, 286 Dipnoans, 346 Discina, 324 Dismal Swamp, 106 Dogs, 413 Dragon flies, 364 Drift, 18, 113, 416 bowlders of, 420 englacial, 125 extent of, 425 pebbles of, 114, 420 stratified, 423 thickness of, 429 Driftless area, 438 Drowned valleys, 197 Drumlins, 421 Duluth, 436 Dunes, 147 Dust falls, 145 Earth, age of, 292, 298, 302 interior of, 276 Earthquakes, 224, 233 causes of, 233, 237 Charleston, 233 distribution of, 236 geological effects of, 234 India, 236 Japan, 237 New Madrid, 236 Earthworms, 20, 21 Echinoderms, 321, 332, 333, 343, 363 Edentates, 441 Egypt, 98 Electric Peak, 269 Elephants, 410 Elevation, effects of, 85 movements of, 197 Eocene epoch, 395 Epicontinental seas, 318 Erratics, 133, 420 Eskers, 424 Etna, 248, 402 Europe, Pleistocene ice sheet of, 427 Eurypterids, 333, 339, 363, 367 Evolution, 300, 447 Faceted pebbles, 113, 114, 420 Falls of the Ohio, 343 Fan folds, 205 Fault scarps, 219 Faults, 217 Faunas, 299 Feldspar, 9, 10, 42 Ferns, 361 Finger lakes, 432 Fire clay, 353 Fishes, 334, 339, 345, 364, 405 Fissure eruptions, 242 Fissure springs, 44 Fjords, 139, 142 Flint, 18, 375 Flood plains, 85, 93 Floods, 54 Floras, 299 Florida, 46, 163, 177, 178, 188, 396 Flow lines, 252 Fluorite, 287 Folded mountains, 210 Folds, 201, 208 Foliation, 283 Foraminifera, 187, 374: Forests, Carboniferous, 354, 361 Cretaceous, 377, 378 Devonian, 343 Tertiary, 404 Fort Wayne, 436 Fossils, 177, 296 Fractures, 215 Fragmental rocks, 8 France, 167, 171 cave men of, 445 Fringing reefs, 190 Frogs, 383 Frost, 15 Fundy, Bay of, 182