452 THE ANTIQUITY OF MAN 
great degree of reduction, limiting greatly the tongue 
space, the lower margin has really increased, giving a 
greater width to the floor space of the mouth. Such a 
change will give greater freedom to the tongue in the 
articulation of words. In both the Piltdown and Heidel- 
berg jaws, especially in the former, the condition of the 
floor of the mouth, in shape and size, is simian or ape- 
like ; the characteristic modern changes have not yet 
appeared in the mandibles of those ancient types. 
Thus in our scrutiny and reconstruction of the Piltdown 
mandible, although we have come across many details of 
structure which seem to suggest that it formed part of 
an anthropoid rather than of a human being, we have met 
with no feature which clearly debars it from being placed 
with the skull. It was found in the same stratum and near 
the skull, and has certain characters which appear to me 
to prevent us from reconstructing it purely on anthropoid 
lines. We can with some confidence assume we are 
dealing with parts of one individual ; our difficulties are 
infinitely greater if we try to allocate the skull to a 
human being and the mandible to an unknown kind of 
anthropoid. 
