ANCIENT MAN IN AFRICA AND JAVA 269 
development of the brain came last. Even in Pithec- 
anthropus the parts of the brain connected with the 
faculty of speech are present ; whether speech was 
actually evolved is a moot point ; at least we may think 
the potentiality was there. 
All the structural characters of Pithecanthropus, so far 
as we know them, are exactly of the kind we expect 
to tind in an early ancestral type of man. Does 
Pithecanthropus, then, represent the stage of evolution 
mankind had reached at the end of the Pliocene period ? 
Can we conceive, keeping in mind the extraordinary 
complexity of the modern human brain, that the simple 
brain, human in form as it is, could have expanded into 
the brain of modern man, with its crowded, highly 
evolved " association " areas, in the course of the 
Pleistocene period ? We know for certain that men 
of different species — Neanderthal and modern — were 
evolved by the middle of the Pleistocene period with 
brains just as complex in form and large in size as the 
modern brain. We have seen that a period of ten, 
twenty, or thirty thousand years can pass and leave the 
human brain almost unaltered. Can we conceive that 
in the stretch of time between the end of the Pliocene 
and the middle of the Pleistocene, even allowing two or 
three hundred thousand years for that space, the brain of 
Pithecanthropus could have evolved into the modern 
human form ? I cannot conceive such a rapid rate of 
evolution. 
We see, however, in all forms of animal life the 
persistence of certain archaic types — certain groups of 
animals retain the characters of an ancient stock, while 
their cousins or collaterals branch out into new forms. 
The fish is an older form than the amphibian, the 
amphibian is older than the mammal, but all three types 
still survive. The gorilla of to-day is not a human 
ancestor, but retains, we suppose, in a much higher 
degree than man does, the stock from which both arose. 
It is in that light I would interpret Pithecanthropus ; 
a true survival, into late Pliocene or early Pleistocene 
