414 THE ANTIQUITY OF MAN 
by the vault and examine such indications as are apparent 
on the frontal and parietal lobes, our statements become 
less certain. The two upper frontal convolutions, so far 
as they are preserved, were apparently simple, but not 
small. The convolution of the central region — where 
the centres for movement and common sensation have 
their seat — are not sharply indicated on the cast ; they 
certainly were not highly developed. On the hinder 
region of the vault the parietal eminence is well marked. 
In position and extent, the raised convolutions which 
form this eminence do not differ from those seen in brain 
casts taken from modern skulls. I cannot detect any 
feature in the frontal, parietal, or occipital areas which 
clearly separates this brain cast from modern ones ; nor 
can I recognise any feature which has a distinct claim to 
be regarded as simian or primitive. A survey of the 
convolutionary regions of the brain leads to the conclusion 
that we are dealing here with a simple and primitive 
arrangement of parts ; but not so simple or so primitive 
as to make us wish to place the Piltdown brain in a 
class apart from modern human brains. To my mind 
it appears, even in its convolutionary arrangement, to fall 
well within the limits of variation seen in modern human 
brains. 
We have been studying the brain as it presents itself 
to us in a side view. A cursory survey of the brain casts 
from behind will prove instructive at this stage of our 
inquiry. We are thus provided with an opportunity of 
surveying both hemispheres of the brain — the right and 
left — and of dealing with the problems relating to their 
symmetry. The right and left halves of the body are 
built so as to match each other, but if we use one side 
more than the other or differently to the other, then we 
expect a certain degree of asymmetry to appear. The 
right and left halves will no longer remain exact counter- 
parts, either in function or in form. A difference in 
form indicates a difference in function. If we are right- 
handed, then the right side of the body preponderates. 
There is a crossing of the nerve tracts of the body, and 
