THE PILTDOWN MANDIBLE 431 
formed part as more anthropoid than human in nature. 
But when we take into account (i) that this mandible lay- 
in the same ancient stratum, and at the same spot as 
an ancient type of man ; (2) that as regards pro- 
portionate size, texture of bone, degree of fossilisation, 
it agrees perfectly with the skull ; (3) that the molar 
teeth are essentially human, I think we must regard 
it as part of the same individual. If we do not, then we 
have to accept the much greater improbability that long 
ago there lived in Sussex (i) a true but early form of man, 
represented by a skull ; (2) an anthropoid with very 
human molar teeth, represented by a lower jaw ; (3) that 
after death the skull of the one and the mandible of the 
other came to rest cheek by jowl in the Piltdown gravel. 
That, of course, is possible, but highly improbable. 
On the other hand, that we should find a human form 
which, in some of its parts, retained or exhibited a marked 
preponderance of simian characters in such a structure 
as the lower jaw is not improbable. A close study of the 
anatomy of man, and of the animals most nearly allied 
to him, shows many examples of this kind. I can 
make my meaning more easily understood if I cite 
a few concrete examples selected from the anthropoid 
apes which show a very close structural relationship to 
man. The chimpanzee's teeth are less specialised, more 
primitive or monkey-like, than those of the gorilla. As 
regards characters of teeth, man and the chimpanzee have 
rather more in common than either has with the gorilla. 
In the anatomy of the lower Hmbs the case is reversed. 
The lower limbs of man are by far the most specialised, 
but the gorilla's also show several human peculiarities 
which are absent in the chimpanzee. As regards the 
characters of the lower limb, we would link man with 
the gorilla. As regards teeth, we would link him with 
the chimpanzee. I will cite two other examples which 
occur to me. In all lower forms of apes the liver is 
divided by deep clefts or fissures into three main lobes — 
right, middle, and left. In all the higher primates — man 
and anthropoids — the triple division of the liver has dis- 
