502 THE ANTIQUITY OF MAN 
type in Asia because they have never been sought for. 
The North American Indian, whom we regard as a 
derivative of the Mongolian type, was certainly evolved 
before the close of the Pleistocene period. Indeed, our 
knowledge of ancestral forms is confined to almost a 
single type — the European. That type, as we have 
already seen, was in existence by the middle of the 
Pleistocene period. In some of the ancient Europeans, 
such as those found at Cromagnon and at Grimaldi, 
negroid traits can be recognised. At present the 
Mediterranean forms the boundary line between the 
European and African types. One can readily believe 
that in former times the African type may have spread 
some distance into Europe. 
As already said, the genealogical tree depicted in fig. 
187 represents a working hypothesis, nothing more. 
When we try to represent in such a form the structural 
relationship between existing and extinct human races 
we again feel the necessity of postulating a great antiquity 
for man. That becomes evident when we come to fit 
the phylum of Neanderthal man into the genealogical 
tree of the human family (fig. 187). He was so different 
from modern man in every point of structure that, in order 
to account for his structural peculiarities, we have to 
represent his phylum as separating from that of the 
modern human type at an early date. In fig. 187 it 
will be seen that 1 have shown the separation as having 
occurred before the middle of the Pliocene period. My 
reasons for selecting so early a date are : (i) that we must 
presume that man of the modern type was evolved by 
the end of the Pliocene period in order to account for 
the differentiation and distribution of the present races 
of mankind ; (2) that the discovery of the Heidelberg 
mandible indicates the existence of a Neanderthaloid type 
of man at the commencement of the Pleistocene period. 
I am thus presuming that before the middle of the 
Pliocene period there was in existence a type of man 
sufficiently high to serve as a common ancestor for the 
Neanderthal and modern species of man. 
I 
