88 READINGS IN EVOLUTION, GENETICS, AND EUGENICS 
vision were well developed there was a limited faculty for profiting 
by experience and accumulated tradition. The femur associated with 
Fic. 7.—Jaws, left outer aspect, of A, 
chimpanzee, Pan, sp.; B, fossil chimpanzee, 
Pan vetus, found in association with Pilt- 
down man; C, Heidelberg man, Homo 
heidelbergensis; D, modern man, H. sapiens. 
(From Lull, after Woodward.) 
the skull is remarkable for its 
length and slight curvature as 
compared with the primitive 
Neanderthal race of Europe 
and indicates a creature fully 
as erect and nearly as tall as the 
average European of today, 
the height being estimated at 5 
feet 7 inches as compared with 
5 feet 3 inches for the Nean- 
derthals and 5 feet 8 inches, 
the average height of modern 
males. The erect posture of 
course implies the liberation 
of the hands from any part in 
the locomotor function. The 
teeth are somewhat ape-like, 
but are more human than are 
those of the gibbon, and the 
human mode of mastication 
has been acquired. Certain 
authorities have tried to prove 
that Pithecanthropus is nothing 
but a large gibbon, but the 
weight of authority considers 
it prehuman, though not in 
the line of direct development 
intohumanity. Itisneverthe- 
less a highly important transi- 
tional form. 
Associated with the Pithe- 
canthropus remains are those 
of a number of the contem- 
porary animals which fix the 
- dateas either of the Upper Plio- 
cene or lowermost Pleistoceen 
period, which being rendered 
in terms of years gives an esti- ; 
mated age of about 500,000! 
