Part 18

Elephas ganesa, tusks, 196

Encrustations, 14

Extermination. See Extinction

Extinction, ascribed to great convulsions, 225 ascribed to primitive man, 188, 224 of Dinosaurs, 221 local, 225 by man, 224, 225 of Marine Reptiles, 222 often unaccountable, 222, 223 of Pliocene rhinoceros, 232 sometimes evolution, 221, 226 of Titanotheres, 222

Feathers, imprints of, 76, 132

Fishes, abundance of, 25 armored, 23, 24, 25, 28 collections of, 32 killed by cold, 230 killed by volcanoes, 231

Fish-crows, killed by cold, 231

Flesh does not petrify, 10

Flightless birds, absent from Tasmania, 155 present distribution, 154, 155 relation between flightlessness and size, 156

Folds and frills, 129

Footprints, collections of, 47 books on, 47 See also under Tracks

Fossil birds, rarity of, 86

Fossil man, 13

Fossilization a slow process, 10

Fossils, conditions under which they are formed, 5, 7 collecting, 112-116 definition of, 1 deformation of, 16 impressions, 2, 3 not necessarily petrifactions, 2 preparation of, 117-119 why they are not more common, 5, 15, 16

Fowls, muscles of, 81

Frill of Triceratops, 102

Fur-seals killed by ice-floes, 233

Gar pikes, destruction of, 26

Giant birds, reasons for distribution and flightlessness, 153

Giant Moa, 141 leg compared with that of horse, 152*

Giant Sloth, domesticated by man, 224 struggle between, 46

Giant Sloth, tracks at Carson City, 46

Gilfort, Robert, 157

Great Auk, extermination of, 232

Grouse on Scotch moors, 235

Hawkins, B. W., restorations by, 137

Hesperornis, description of, 80 impressions of feathers, 132 position of legs, 83, 84 restoration of, 82*