FOSSIL MEN. 297 
investigations of a future time. This applies also to those 
more special questions of human phylogeny at which it 
is desirable before concluding to take a cursory glance, 
namely, the question of the time and place of the origin of 
the human race, as also of the different species and races 
into which it has differentiated. | 
In the first place, the period of the earth’s history, within 
which the slow and gradual transmutation of the most 
man-like apes into the most ape-like men took place, can of 
course not be determined by years, nor even by centuries. 
This much can, however, with full assurance be maintained, 
for reasons given in the last chapter, that Man is derived 
from Placental animals. Now, as fossil remains of these 
Placentalia are found only in the tertiary rocks, the 
human race can at the earliest have developed only within 
the Tertiary period out of perfected man-like apes, What 
seems most probable is that this most important process in 
the history of terrestrial creation occurred towards the end 
of the Tertiary period, that is in the Pliocene, perhaps even 
in the Miocene period, but possibly also not until the 
beginning of the Diluvial period. At all events Man, as 
such, lived in central Europe as early as the Diluvial period, 
contemporaneously with many large, long since extinct 
mammals, especially with the diluvial elephant, or mammoth 
' (Elephas primigenius), the woolly-haired rhinoceros (Rhino- 
ceros tichorrhinus), the giant deer (Cervus euryceros), the 
cave bear (Ursus speleeus), the cave hyzena (Hyzena spelzea). 
the cave lion (Felis spelzeus), etc. The results brought to 
light by recent geology and archeology as to these fossil 
men and their animal contemporaries of the diluvial period, 
are of the greatest interest. But as a closer examination of 
