LIST OF ILLUSTRATIONS xiii 



PIG. PAGE 



81. THE SKULL OF A MALE CHIMPANZEE . . .405 



82. THE HEIDELBERG JAW . . . . . 405 



PLATES 



I. IMMATURE AND MATURE SPECIMENS OF THE 



COMMON EEL OF THE NATURAL SIZE . . Frontispiece 



II. REAL DRAGONS. THE EXTINCT FLYING REPTILES 



KNOWN AS PTERODACTYLES . . Facing p. 118 



