303 
TX, 
THE DEVELOPMENT OF HUMAN RACES 
UNDER THE LAW OF NATURAL SELEC- 
TION. 
Amone the most advanced students of man, there exists 
a wide difference of opinion on some of the most vital 
questions respecting his nature and origin. Anthro- 
pologists are now, indeed, pretty well agreed that man 
is not a recent introduction into the earth. All who 
have studied the question, now admit that his anti- 
quity is very great; and that, though we have to some 
extent ascertained the minimum of time during which 
he must have existed, we have made no approximation 
towards determining that far greater period during 
which he may have, and probably fas existed. We 
can with tolerable certainty affirm that man must have 
inhabited the earth a thousand centuries ago, but we 
cannot assert that he positively did not exist, or that 
there is any good evidence against his having existed, 
for a period of ten thousand centuries. We know 
positively, that he was contemporaneous with many 
now extinct animals, and has survived changes of the 
earth’s surface fifty or a hundred times greater than 
any that have occurred during the historical period; 
but we cannot place any definite limit to the number 
“ 
