THE BONY FISH, AND HOW THEY HAVE SPREAD OVER SEA, AND LAKE, AND RIVER 43 PICTURE-HEADING--Restorations of _Osmeroides_ and _Beryx_, the earliest known bony fishes living in the Cretaceous Period. (From well-known figures.) CHAPTER IV. HOW THE BACKBONED ANIMALS PASS FROM WATER-BREATHING TO AIR-BREATHING, AND FIND THEIR WAY OUT UPON THE LAND 70 PICTURE-HEADING--A Carboniferous Forest with ancient Amphibians (Labyrinthodonts). In the water _Baphetes_; on land _Dendrerpeton_, _Hylonomus_, and _Hylerpeton_. (Animals taken from Dawson’s _Air-Breathers of the Coal_.) CHAPTER V. THE COLD-BLOODED AIR BREATHERS OF THE GLOBE IN TIMES BOTH PAST AND PRESENT 89 PICTURE-HEADING--Reptiles of the Cretaceous Period. On land _Iguanodon_, 20 feet high, attacked by _Megalosaurus_; in the air _Pterodactyls_, or flying lizards; in the water _Ichthyosaurus_, _Mosasaurus_, and _Teleosaurus_, with _Plesiosaurus_ in the background. (From various sources.) CHAPTER VI. THE FEATHERED CONQUERORS OF THE AIR--PART I. THEIR WANDERINGS OVER SEA AND MARSH, DESERT AND PLAIN 123 PICTURE-HEADING--Toothed Water-birds of the Cretaceous Period. Swimming and standing, _Hesperornis_; flying, _Ichthyornis_. (Restored from Marsh’s Skeletons.) CHAPTER VII. THE FEATHERED CONQUERORS OF THE AIR--PART II. FROM RUNNING TO FLYING, FROM MOUND LAYING TO NEST-BUILDING, FROM CRY TO SONG 153 PICTURE-HEADING--_Archæopteryx_, the lizard-tailed land-bird with teeth. (Restored from figures of the British Museum and German specimens.) CHAPTER VIII. THE MAMMALIA OR MILK-GIVERS, THE SIMPLEST SUCKLING MOTHER, THE ACTIVE POUCH-BEARERS, AND THE IMPERFECT-TOOTHED ANIMALS 181 PICTURE-HEADING--Scene in the Triassic Period, with small Marsupials _Microlestes_, whose remains are found earlier than the toothed birds. (Restored conjecturally from the nearest living representative, Myrmecobius.) In the water large swimming reptiles. CHAPTER IX. FROM THE LOWER AND SMALL MILK-GIVERS WHICH FIND SAFETY IN CONCEALMENT, TO THE INTELLIGENT APES AND MONKEYS 209 PICTURE-HEADING--Ideal forms of the early Herbivora and Carnivora. In the foreground _Paleotherium_, _Anoplotherium_, and _Eohippus_ (this last only restored conjecturally); in the background, _Xiphodon_ and _Arctocyon_ (this last also only an approximation); on the tree, a small lemur; and in front, a hedgehog. CHAPTER X.