428 TROPICAL NATURE vil 
prominence. Other examples have the nose somewhat pro- 
jecting at the apex in a manner quite unlike the features of 
any American indigenes; and although there are some which 
show a much coarser face, it is very difficult to see in any of 
them that close resemblance to the Indian type which these 
sculptures have been said to exhibit. The few authentic 
crania from the mounds present corresponding features, being 
far more symmetrical and better developed in the frontal 
region than those of any American tribes, although somewhat 
resembling them in the occipital outline; while one was 
described by its discoverer (Mr. W. Marshall Anderson) as a 
“beautiful skull, worthy of a Greek.” 
The antiquity of this remarkable race may perhaps not 
be very great as compared with the prehistoric man of Europe, 
although the opinion of some writers on the subject seems 
affected by that ‘parsimony of time” on which the late Sir 
Charles Lyell so often dilated. The mounds are all over- 
grown with dense forest, and one of the large trees was 
estimated to be 800 years old, while other observers consider 
the forest growth to indicate an age of at least 1000 years. 
But it is well known that it requires several generations of 
trees to pass away before the growth on a deserted clearing 
comes to correspond with that of the surrounding virgin 
forest, while this forest, once established, may go on growing 
for an unknown number of thousands of years. The 800 or 
1000 years estimate from the growth of existing vegetation 
is a minimum which has no bearing whatever on the actual 
age of these mounds; and we might almost as well attempt 
to determine the time of the glacial epoch from the age of 
the pines or oaks which now grow on the moraines. 
The important thing for us, however, is that when North 
America was first settled by Europeans, the Indian tribes 
inhabiting it had no knowledge or tradition of any preceding 
race of higher civilisation than themselves. Yet we find that 
such a race existed—that they must have been populous and 
have lived under some established government; while thera 
are signs that they practised agriculture largely, as, indeed, 
they must have done to have supported a population capable 
of executing such gigantic works in such vast profusion ; for 
1 Wilson’s Prehistoric Man, 3d ed., vol. ii. pp. 128-180. 
