1 62 HUMAN BIOLOGY 



yellow-browns; while general dolicho- to meso-cephaly, 

 but reaching in individuals and in some central tribes to 

 brachycephaly, prevails in the African negro. Even the 

 full-blood Australian reaches from extreme dolichocephaly 

 to the border of brachycephaly, and from low skull to high 

 (see Hrdlicka, 1924). 



The skull shape changes between birth and the adult 

 stage; differs in the two sexes; is affected slightly by stature; 

 and has within historic times been observed to gradually 

 change in the same people, particularly in the direction of 

 brachycephaly (Austria, Bohemia, Germany, England, 

 etc.), but also in the opposite direction (the Eskimo). 



The most distinct and least varied skull, on the whole, is 

 that of the African negro. Yet it also shows some marked 

 differences, as in the "Boskop" type, which may here and 

 there be observed among the living unmixed negroes in 

 South Africa. And individual negro features occur now and 

 then in the crania of all other races, without admixture. 

 In some respects, such as the nose, and prognathy, the 

 African negro skull is on the whole the most primitive; yet 

 it will occasionally be exceeded even in these features by an 

 Australian or Melanesian; and in some points, such as the 

 reduction of the jaws and particularly that of the supraorbital 

 ridges, it, on the average, exceeds these. In the reduction 

 of the brow ridges it surpasses (which means that it is 

 evolutionally more advanced) even the skull ofthe white man. 



Other Racial Differences 



Much the same conditions of indefmiteness, or imperfect 

 stability, and overlapping, apply to all other characters, 

 of whatever nature, that are better known in man at large. 

 Nothing is fully set, nothing immutable, nothing wholly 

 apart from the rest. Wherefore the conclusion that man is 

 represented today by but one species, and that his sub- 

 divisions deserve no farther reaching designation than that 

 of races, seems the only justifiable conclusion. 



Changes in Racial Characters 



Races are more or less definite hereditary complexes. 

 Their characters may be viewed as so many acquisitions 



