ANATOMICAL PECULIARITIES 143 
supra-orbital ridges, because we could not cite a better 
instance of the kind of evidence we have to use in tracing 
the genealogy of man. We might explain the presence 
of a torus form of supra-orbital ridge in Neanderthal 
man by supposing he has arisen from a gorilla-like stock, 
and modern man from a monkey-like ancestry. That 
would explain why modern man has a forehead of one 
form and Neanderthal man one of quite another type. 
We should thus fall back, as Professor Klaatsch ^ has 
done, on the theory that mankind is multiple in origin — 
that one human race has been evolved from one ancient 
stock of primates, while another race has arisen from 
another and quite different simian stock. But in success- 
fully explaining this one and minor feature we should 
find, if we accept a " polyphyletic theory " of man's 
origin, that the great majority of structural relationships 
were not capable of being thus explained. We must 
take all the characters of the human body into considera- 
tion, not one or more isolated features, and when we do 
so it is plain that the Neanderthal type and the modern 
type of man share the great common inheritance of human 
characters. We must suppose that this community of 
structure is due to a community of origin — to the fact that 
they arise from a common ancestor. Further, when we 
begin to analyse the structural nature of man and his 
nearest allies — the gorilla, chimpanzee, and orang — we 
find he shares so much with them, much more than with 
old-world or new-world monkeys, that, to explain the 
widespread community of structure, we are compelled 
to suppose the great anthropoids and all human forms, 
living and fossil, to have arisen from a common stock. 
Now in that common stock from which anthropoids and 
men have been evolved we have reason to believe that 
the torus form of supra-orbital ridge was a character. 
In the ancestry of modern races it has been modified. 
Indeed, in many living peoples there is a tendency to 
assume the condition seen in foetal or infantile stages, where 
those ridges are still undeveloped. In Neanderthal man, 
' See Nature, 191 i, vol. Ixxxv. p. 508. 
