_=The Times=_: “There has been published no book on this subject combining so successfully the virtues of accuracy and attractiveness.... Dr. Lankester’s methods as an expositor are well known, but they have never been more pleasantly exemplified than in the present book.” _=The Athenæum=_: “Examples of Extinct Animals and their living representatives Professor Lankester has described with a masterly hand in these present pages.” LONDON ARCHIBALD CONSTABLE & CO LTD 10 ORANGE STREET, LEICESTER SQUARE * * * * * * Eyre & Spottiswoode, H.M. Printers, London DESCRIPTION OF THE FRONTISPIECE The upper figure is from a cast of the celebrated specimen found in a river gravel in Java, probably of as great age as the palæolithic gravels of Europe. Though rightly to be regarded as a ‘man’--the creature which possessed this skull has been given the name ‘_Pithecanthropus_.’ The shape of the cranial dome differs from that of a well-developed European human skull (shewn in the lower photograph, that of a Greek skull) in the same features as do the very ancient prehistoric skulls from the Belgian caves of Spey, and from the Neanderthal of the Rhineland. These differences are, however, measurably greater in the Javanese skull. The three great features of difference are: (1) the great size of the eye-brow ridges (the part below and in front of A in the figures) in the Java skull; (2) the much greater relative height of the middle and back part of the cranial dome (lines _e_ and _f_) in the Greek skull; (3) the much greater prominence in the Greek skull of the front part of the cranial dome--the prefrontal area or frontal ‘boss’ (the part in front of the line A C, the depth of which is shewn by the line _d_). The parts of the cranial cavity thus obviously more capacious in the Greek skull are precisely those which are small in the Apes and overlie those convolutions of the brain which have been specially developed in Man as compared with the highest Apes. The line A B in both the figures is the ophryo-tentorial line. It is drawn from the ophryon (the mid-point in the line drawn across the narrowest part of the frontal bone just above the eye-brow ridges), which corresponds externally to the most anterior limit of the brain, to the extra-tentorial point (between the occipital ridges) and is practically the base line of the cerebrum. The lines _e_ and _f_ are perpendiculars on this base line, the first half-way between A and B, the second half-way between the first and the extra-tentorial point. C is the point known to craniologists as ‘bregma,’ the meeting point of the frontal and the two parietal bones.