THE HUMAN SPECIES. 121 



species overlapped, strove for possession, and were 

 forced to withdraw or to submit to absorption. Periods 

 of repose seem even to be requisite before new in- 

 fluences are efficient ; and thus, by degrees, commences 

 that state of amalgamation which the necessities of the 

 case, and the conditions already mentioned, prescribe 

 to generate secondary forms of Man, by combinations, 

 where new habits, new dialects, new articles of food, 

 together with at least change of climate in one of the 

 constituents, had their legitimate sphere of action. It 

 is thus, where the foreign influence of infusion is mo- 

 dified by a change of climate, that mixed races spring 

 up and have a continuous duration beyond the pale of 

 their primitive centres of existence, until the ground 

 is contested by the purer races, when they fall a prey 

 to the victors, are exterminated, absorbed, or perish 

 by a kind of decreasing vitality, or are entirely obli- 

 terated.* 



The centres of existence of the three typical forms 

 of man, are evidently the intertropical region of 

 Africa, for the woolly haired the open elevated regions 

 of north-eastern Asia for the beardless and the moun- 

 tain ranges towards the south and west for the bearded 

 Caucasian. But, with regard to the western hemis- 

 phere, it may be asserted, that it is not a centre of any 

 typical stock, since the primeval Flatheads have already 



* Yet this apparent obliteration must ever affect sub- 

 sequent forms and mental conditions in the victors, which 

 the physiologist ought to bear in mind, where known, or 

 indicate when only suspected. 



