INDEX 



705 



Heliophyllum halli, 456. 



Hematite, 686. 



Hemipristis serra, 625. 



Hemiptera, 533. 



Hercoglossa tuomeyi, 628. 



Hesperornis, 561-562. 



Heterocrinus (Iocrinus) subcrassus, 431. 



Hexacorolla, 524. 



Hidden Glacier, 179. 



High plains, 588. 



Hillside creep, 73. 



Hinge fault, 282. 



Hipparion, 610. 



Hipparionyx proximus, 458. 



Hippopotamus amphibius, 6j6. 



Historical geology, definition of, 22. 



Hoang Ho, delta of, 132, 133. 



destructiveness of, 123. 

 Hobbs, W. H., 33, 285, 287. 

 Hogback, 105. 

 Holoptychius, 465. 

 Hooks, 220-221. 

 Horizontal faults, 264-265. 

 Hormatoma gracilis, 434. 

 Hornblende, 690. 



schist, 346. 

 Horses, evolution of, 608-612. 



extinction of in North America, 611- 

 612. 



Pleistocene, 672. 

 Horseshoe lakes, 122. 

 Horsetails, 565. 

 Horst, 263, 354. 

 Hot springs, 66. 



Hudson River, Palisades of, 326, 511. 

 Humboldt Glacier, Greenland, 170. 

 Huronian system, 393. 

 Hustedia mormoni, 482. 

 Hybocrinus tumidus, 431. 

 Hydration, 36. 

 Hydrographical basins, 103. 

 Hymenocaris perfecta, 412. 

 Hyolithes carinatus, 413. 

 Hypohippus, 610. 

 Hypothyris cuboides, 458. 

 Hyracodon, 606. 



Ice, formation from snow, 142. 

 in lakes, 204. 

 in sea, 203. 

 texture of, 142-143. 



Icebergs, formation of, 188. 



Icebergs — (Continued) 



size of, 189, 190. 



work of, 189. 

 Icefalls on glaciers, 148, 149. 

 Icelandic volcanoes, 311. 

 Ice sheets, 168-171. 



centers of, 646-647. 



deposition by, 171-182. 



development of, 647-648. 



effect on drainage, 184-188. 

 on rivers, 187. 



erosion by, 182-184. 



in foreign countries, 645. 



in North America, 176, 646-647. 



moraines of, 175. 



thickness of, 647-648. 



work of, 662-663. 

 Ice tables on glaciers, 149, 150. 

 Ichthyornis, 562-563. 

 Ichthyosaurus, 553-554. 

 Igneous intrusions, and ore deposits, 

 372. 



rocks, age of, 334. 

 definition of, 24. 

 subdivisions of, 329. 

 weathering of, 32. 

 Iguanodon, 544. 

 Illinoian epoch, 649. 

 Impact marks, 75. 

 Imperial valley, Cal., 132. 

 Incompetent strata, 257. 

 Industrial geology, definition of, 22. 

 Injected igneous rock, 324-327. 

 Inoceramus, 528. 

 Inoceramus vanuxemi, 527. 

 Inostranservia, 539. 

 Insectivores, 620. 

 Insects, Carboniferous, 481, 484. 



Mesozoic, 532-533. 



Tertiary, 627-630. 

 Interglacial deposits, 664-665. 



migrations, 665. 



stages, 648-649. 

 Interior heat, 273, 365. 

 Interior of earth, 272-274, 335, 365. 

 Intermittent springs, 64. 

 Internal density, theories of, 273. 

 Internal fluidity theory, 273. 

 Intrenched meanders, 112. 

 Intrusions of lava, 324-328. 

 Iowan stage, 649. 

 Iron minerals, 686-687. 

 Iron ore, Clinton, 442. 



