OSTEOMETRY; THE MEASUREMENT OF THE BONES 71 



involved, but does not measure quite the same thing, and cannot be sub- 

 stituted for it. It measures the inclination of the frontal chord (the 

 line nasion-bregma) to the nasion-inion line. Schwalbe, who first em- 

 ployed it under the name of the Bregma angle, measured it upon a cranio- 

 gram, but it may equally well be measured direct by first setting the 

 skull upon the nasion-inion, instead of the FH, as a horizontal, and then 

 measuring with the goniometer, one foot each upon nasion and bregma. 

 CG or GO. 



4. Occipital inclination angle [= "Lambda angle" of Schwalbe]. 

 The inclination of the lambda-inion to the nasion-inion line. This is 

 best drawn upon the craniogram, as is done with the Frontal inclination 

 angle, its counterpart at the other end of the nasion-inion. These 

 two angles, which fix definitely the position of the frontal and occipital 

 bones, respectively, were called by G. Schwalbe, who first proposed 

 them, the " bregma" and "lambda" angles, evidently forgetting for the 

 moment that ang'es are usually named from the point that forms their 

 apex. He also used the glabella-inion, instead of nasion-inion, in accord- 

 ance with the usage of the time.* 



As with the frontal inclination angle, this may also be measured upon 

 a skull, set upon the FH, by means of the stationary goniometer, the two 

 points of which rest upon lambda and inion. CG or GO. 



5. Facial profile angle [The modern equivalent of the facial angle of 

 Camper 1- The inclination of the nasion-prosthion line to the FH. 

 Use as prosthion the most projecting point of the alveolar border in the 

 median line and measure with the stationary goniometer. In a skull with 

 a seriously damaged alveolar border this angle cannot be taken. The 

 angles have the following values: 



hypei prognathous below 7 



prognathous 70-80 



mesognathous 80-85 



orthognathous 85-93 



hyperorthognathous 93 + 



This angle gives the inclination of the line used in calculating the superior 

 facial index (index No. 16) and as it includes the slant of the entire upper 

 face, it is very important, especially as a racial criterion. It was about 

 this angle, roughly estimated, and very imperfectly designated, that was 

 used by Petrus Camper as his famous Facial Angle, which yielded such 

 definite results as a racial criterion, and may be considered the beginning 

 of the modern science of anthropometry. GO. 



6. Nasal profile angle. Similar to the last, -but with a shorter line 

 subtending the angle, that of the nasal length, instead of the superior 



* For the frontal inclination angle cf. Zeitschr. fur Morphol. und Anthropol. 

 Bd. I, 1899. p. 142. For the occipital inclination angle cf. Zeitschr. fur Morphol 

 und Anthropol. Sonderheft, 1906. p. 20. 



