INDEX 



701 



Dip and strike, 252. 

 Dipleura dekayi, 460. 

 Diplograptus pristis, 428. 

 Diplopodia texanum, 526. 

 Diptera, 533. 



Dirt cones on glaciers, 150. 

 Displacement of faults, 262, 281, 282. 

 Distributaries, on alluvial cones, 126. 



on deltas, 130. 

 Divides, 103. 

 Divisional planes, 25. 

 Dole and Stabler, 83. 

 Dolichopterus macrocheirus, 449. 

 Dolines, 73. 

 Dolomite, 249, 687. 

 Domed mountains, 355-356. 

 Don stage, 664. 



Dovetailing of sediments, 239-240. 

 Downthrow of fault, 262. 

 Dreikanter, 45. 

 Driftless area, 174. 

 Drift sheets, characteristics of ancient, 



650-651. 

 Dromatherium, 563-564. 

 Drowned rivers, 114. 

 Drumlins, 177. 

 Dryopithecus, 622. 

 Duna River, rapid erosion by, 96. 

 Dunbar, storm waves at, 201. 

 Dunes, 46-52. 



beneficial effects of, 51. 



distribution of, 46. 



height of, 52. 



material of, 51. 



migration of, 49-51. 



origin of, 47, 48, 49. 



shape of, 47, 48, 49. 



structure of, 47. 

 Dunwich, England, marine erosion at, 



213. 

 Dust, origin of, 54. 



wind-blown, 52-54. 

 Dust wells on glaciers, 150. 

 Dynamical geology, definition of, 21. 



Earth, future habitability of, 683-684. 



interior of, 272-274. 



origin of, 385-387- 



specific gravity of, 273-275, 387. 

 Earthquake, craterlets, 291. 



gases, 291. 



rift of California, 275-278, 286, 289. 



Earthquake — (Continued) 



topography, 289. 



vibrations, amplitude of, 284. 



waves, 202, 283. 

 Earthquakes, areas affected by, 286. 



causes of, 281. 



construction of buildings in regions 

 affected by, 291-292. 



destruction by, 275, 290. 



distribution of, 278-280. 



duration of, 286. 



focus of, 282. 



frequency of, 286. 



geological effects of, 287-291. 



great sea waves caused by, 292. 



sounds accompanying, 290. 



vorticose movements of, 285. 

 Eatonia medialis, 458. 

 Echinocaris punctata, 460. 

 Echinodermata, Cambrian, 415. 



Carboniferous, 480, 481. 



Devonian, 457. 



Ordovician, 430-431. 



Silurian, 445-446. 

 Echinoids, Carboniferous, 480. 



Mesozoic, 525-526. 



Tertiary, 626, 627. 

 Economic geology, definition of, 22. 

 Ecphora quadricostata, 628. 

 Ectenocrinus grandis, 431. 

 Eddystone lighthouse, England, 203. 

 Edentates, Mesozoic, 621-622. 



Pleistocene, 670-671. 

 Elasmosaurus, 554. 

 Elephants, 612-615. 

 Elephas antiquus, 676. 



primigenius, 668. 

 Elevation, effect on streams, ill. 

 Endoceras, 435. 

 Endothiodon, 537. 

 Englacial debris, 156. 

 Enostracophori, 464. 

 Entelodon, 619. 

 Eobasileus, 593. 

 Eocene epoch, 574. 



climate of, 634-635. 



close of, 576. 



coal in, 575. 



migration during, 639. 



of Atlantic and Gulf coasts, 574. 



of other continents, 576-577. 



of Pacific coast, 574-575. 



of western interior, 575-576. 



