182 DOCTRINE OF EVOLUTION 



elliptical in cross-section, and when they emerge from 

 the skin they grow into a long spiral. If, now, the hair 

 is formed as a very much flattened rod about one-half 

 as wide in one diameter as in the other, it curls into a 

 very tight close spiral and gives the frizzly or woolly 

 head-covering of the Papuan and of the Negro. 



In the next place, the shape of the cranium is a char- 

 acter of much value. This is determined as the propor- 

 tion between the transverse diameter of the skull above 

 the ears to the long diameter, namely, the line that runs 

 from the middle of the brow to the most posterior point 

 of the skull. In the so-called '4ong-headed " or doli- 

 chocephalic races, the proportion is seventy-five to one 

 hundred, while in those forms that have more rounded 

 or brachy cephalic heads, like the Polynesian and the 

 black pygmy, the relation is eighty-three to one hundred. 

 The cranial capacity again varies considerably, from 

 nine hundred cubic centimeters to twenty-two hundred 

 cubic centimeters. Many striking variations are also 

 found in the projection of the jaws. A line drawn 

 from the lower end of the nose to the chin makes a 

 certain angle with the line drawn from the chin to the 

 posterior end of the lower jaw; if the jaw projects very 

 greatly, this angle will be much less than when they do 

 not. In most of the Caucasian peoples, the lines meet 

 at an angle of eighty-nine degrees, or very nearly a right 

 angle, but in some of the lower races the figure may be 

 only fifty-one degrees. Additional characters of the 

 teeth and of the palate are also taken into account, and 

 have proved their utility. Finally, the nose exhibits 

 a wide range of variation from the small delicate feature 

 of the Chinaman to the large, well-arched nose of the 



