Horse, abundant in Pleistocene time, 164 books on, 176 of bronze age, 163, 167 collections of fossil, 176 development of, 167, 168,* 175 differences between fossil and living, 163 early domestication, 165 evidence as to genealogy, 170-173 extra-toed, 172, 173 found in South America in 1530, 165 of Julius Caesar, 172 none found wild in historic times, 165 Pliocene, 166 possibility of existence in America up to the time of its discovery, 169, 170 primitive, 160, 161* Horse, sketched by primitive man, 163 teeth of, 170 three-toed, 166 Humming-bird, exterminated by hurricane, 231 Hydrarchus, 62* Hyracotherium, 160, 161,* 170, 174 Ichthyosaurs, silhouettes of, 132 Iguanodons, found at Bernissart, 104 Impressions of feathers, 131 of scales, 131 of skin, 131 Inbreeding, effects of, 231, 232 Information, sources of, xvi Innuits, habits, 192 Interdependence of animals and plants, 234, 235, 238 Ivory, fossil, 2, 4, 188, 189 Jaw of Mosasaur, 54* of reptiles, 53 Killing of the Mammoth, story, 177, 193 Kimmswick, deposit of Mastodon bones, 209 Knight, Charles R., restorations by, xviii, 136 Koch's Hydrarchus, 61, 62* Missourium, 207,* 208 Leaves, impressions of, 3, 13 Leg of Brontornis, 149* Leg of the Great Brontosaurus, 96* of Giant Moa, 152* position in Hesperornis, 83 position in ducks, 84 Lenape Stone, 215, 216, 219* Life, earliest traces of, 21, 34 Lingula, antiquity of, 228 Professor Brooks on, 229 Loricaria, 24* Mammoth, adapted to a cold climate, 134 Alaskan Live, Story, 190 believed to live underground, 178 bones taken for those of giants, 185 contemporary with man, 189 derivation of name, 178 description, 179 discovery of entire specimens, 183, 187 distribution, 184, 186 drawn by early man, 189, 197* entire specimens obtainable, 194 reasons for extermination, 188 killing of the, 177 literature on, 197 misconception as to size, 179 mounted skeleton, 179 not now living, 190 preservation of remains, 187 skeletons in Alaska, 181, 195 Mammoth, in Chicago Academy of Sciences, 179 at St. Petersburg, 183* restoration, 176* size, 179, 180, 181 size of tusks, 181, 196 teeth, 196, 199* teeth dredged in North Sea, 184 tusks brought into market, 188, 189 Man contemporary with Mammoth, 189 fossil, 13 of Guadeloupe, 13 Manatees killed by cold, 230 Marsh, Prof. O. C., collection of fossil horses, 176 on Dinosaurs, 222 on toothed birds, 79, 89