eo 
0. Q. Marsh— Vertebrate Lage in America. 375 
The relations of the American Primates, extinct and recent, 
to those of the other hemisphere, offer an inviting topic, but it 
Is not in my present province to discuss them in their most 
suggestive phases, s we have here the oldest and most 
ancestry, is readily explained by the then intervening oceans, 
which likewise were a barrier to the return of the Horse and 
Rhinoceros. : : 
however, came; doubtless first ; across Behring’s 
a ? 
Straits; and at his advent became part our fauna, as a 
mammal and primate. In these relations alone, it is my pur- 
visits to that region, many facts were brought to my knowl- 
edge which render this more than probable. Man at this time 
as a savage, and was doubtless forced by the great volcanic 
outbreaks to continue his migration. This was at first to the 
south, since mountain chains were barriers on the east. As 
the native Horses of America were now all extinct, and as the 
early man did not bring the old world animal with him, his 
migrations were slow. I believe, moreover, that his slow pro- 
gress towards civilization was in no. small degree due to this 
same cause, the absence of the Horse 
typical Mound-builders of the Mississippi Valley and those of 
the Pueblo Indians. I had long been familiar with the former, 
