COMPARISONS OF THE SKELETONS OF HORSE AND MAN 167 Photo: British Museum (Natural History). A RECONSTRUCTION OF THE JAVA MAN (_Coloured Illustration_) 168 PROFILE VIEW OF THE HEAD OF PITHECANTHROPUS, THE JAVA APE-MAN--AN EARLY OFFSHOOT FROM THE MAIN LINE OF MAN'S ASCENT 170 After a model by J. H. McGregor. PILTDOWN SKULL 170 From the reconstruction by J. H. McGregor. SAND-PIT AT MAUER, NEAR HEIDELBERG: DISCOVERY SITE OF THE JAW OF HEIDELBERG MAN 171 Reproduced by permission from Osborn's _Men of the Old Stone Age_. PAINTINGS ON THE ROOF OF THE ALTAMIRA CAVE IN NORTHERN SPAIN, SHOWING A BISON AND A GALLOPING BOAR (_Coloured Illustration_) 172 PILTDOWN MAN, PRECEDING NEANDERTHAL MAN, PERHAPS 100,000 TO 150,000 YEARS AGO 174 After the restoration modelled by J. H. McGregor. THE NEANDERTHAL MAN OF LA CHAPELLE-AUX-SAINTS 175 After the restoration modelled by J. H. McGregor. RESTORATION BY A. FORESTIER OF THE RHODESIAN MAN WHOSE SKULL WAS DISCOVERED IN 1921 176-177 SIDE VIEW OF A PREHISTORIC HUMAN SKULL DISCOVERED IN 1921 IN BROKEN HILL CAVE, NORTHERN RHODESIA 178 Photo: British Museum (Natural History). A CROMAGNON MAN OR CROMAGNARD, REPRESENTATIVE OF A STRONG ARTISTIC RACE LIVING IN THE SOUTH OF FRANCE IN THE UPPER PLEISTOCENE, PERHAPS 25,000 YEARS AGO 178 After the restoration modelled by J. H. McGregor. PHOTOGRAPH SHOWING A NARROW PASSAGE IN THE CAVERN OF FONT-DE-GAUME ON THE BEUNE 179 Reproduced by permission from Osborn's _Men of the Old Stone Age_. A MAMMOTH DRAWN ON THE WALL OF THE FONT-DE-GAUME CAVERN 179 A GRAZING BISON, DELICATELY AND CAREFULLY DRAWN, ENGRAVED ON A WALL OF THE ALTAMIRA CAVE, NORTHERN SPAIN 179 PHOTOGRAPH OF A MEDIAN SECTION THROUGH THE SHELL OF THE PEARLY NAUTILUS 186 PHOTOGRAPH OF THE ENTIRE SHELL OF THE PEARLY NAUTILUS 186 NAUTILUS 186 SHOEBILL 187 Photo: W. S. Berridge. THE WALKING-FISH OR MUD-SKIPPER (_Periophthalmus_), COMMON AT THE MOUTHS OF RIVERS IN TROPICAL AFRICA, ASIA, AND NORTH-WEST AUSTRALIA 190 THE AUSTRALIAN MORE-PORK OR PODARGUS 190 Photo: _The Times_. PELICAN'S BILL, ADAPTED FOR CATCHING AND STORING FISHES 191