74 LABORATORY MANUAL OF ANTHROPOMETRY 



by the line basion-opisthion and the median line of the FH, which is 

 always the line meant in a craniogram involving this horizontal. 



As most forms of craniophore use the occipital foramen to fasten the 

 clamp into which holds the skull, either basion or opisthion or both are 

 not available, a special form of craniophore is devised which takes hold 

 of the skull elsewhere. A thin strip of metal is then attached to both 

 basion or opisthion by wax, plastilena, or some similar substance and the 

 inclination of this strip taken with the goniometer. When the opisthion 

 is higher than the basion the angle made with the FH opens backwards 

 and is marked with a + sign ; when the basion is higher, the angle opens 

 forwards, and is marked with a sign. 



11. Frontal curvature angle. 



12. Parietal curvature angle. 



13. Occipital curvature- angle. 



These angles, all constructed in the same way upon the craniogram, 

 show with considerable precision the shape of the three contour bones of 

 the cranium, as they appear in the median line. In each case the longest 

 perpendicular is erected upon the chord of the bone in question (lines 

 51, 52, and 53 above), and lines drawn from where this perpendicular 

 comes in contact with the contour curve to each end of the chord. The 

 angle thus formed is the angle sought. The greater the angle the flatter 

 the bone. CG. 



14. Occipital flexional angle. This angle, which shows the amount of 

 bend, or flexion of the two parts of the occipital scale, with apex at the 

 inion, is drawn upon the craniogram, by the lines 1-i and i-o, and meas- 

 ured by the protractor. CG. 



15. Superior facial length angle. The angle formed at the basion, 

 by the lines nasion-basion and prosthion -basion (9 and 10), and subtend- 

 ing the superior facial line. Drawn upon the craniogram, and measured 

 by the protractor. CG. 



16. Facial length angle. Similar to the last, but using the line 

 gnathion-basion (34), instead of prosthion-basion, and thus subtending 

 the total, instead of the superior, facial length. Only to be done in 

 skulls with a good mandible, which is set in the proper position, either 

 by a spring or by plastilena, before making the craniogram. CG. 



Aside from angles, certain triangles or higher polygons are readily 

 drawn upon a craniogram, or are constructed (like the triangle n-ba-pr) 

 as a result of the preceding work. The various angles of these may be of 

 some value, yet their further study falls dangerously near the empirical 

 method above mentioned. However, there may be mentioned in this 

 connection one triangle and one quadrilateral, whose position makes them 

 more or less fundamental in describing the shape of a given skull. 



A. The Superior facial triangle (n-ba-pr). This follows and ap- 

 proximately defines the nasal fossa, being bounded by the cranio-basal 



