62 



THE HUMAN SPECIES 



mammals, the anthropoids included, lies in the measurements of 

 the skull in profile. This measurement was formerly based 

 on Camper's facial angle, but since the Frankfort agreement it 



I II in 



FIG. 17. Development of the Human embryo. (Haeckel, Anthropogenic.) 



I II III 



FIG. 18. Development of the Gibbon embryo. (Haeckel, Anthropogenic.) 



takes, in common with all other craniometrical measurements, 

 the German level as basis. 



Camper described a horizontal line passing along the base of 

 the nose and orifice of the external auditory canal, and classi- 



