50 LABORATORY MANUAL OF ANTHROPOMETRY 



other; the maximum transverse diameter, perpendicular to the median 

 plane. Cr. 



4. Cranial height 



(a) basilo-bregmatic (basion-bregma) height; from basion to bregma. 



(b) auriculo-bregmatic height; the difference in level between porion 

 and bregma. Several special forms of instrument have been 

 devised for taking this measurement, but the simplest method, 

 and fairly accurate after a little practice, is that of using the 

 rod compass (the anthropometer put together in a special 

 way (cf. above, under Instruments). The skull is held in the 

 left hand, and the rod compass is held so far as possible in a 

 plane parallel to the median sagittal plane of the skull. The 

 upper leg should be drawn out longer than the lower one, the 

 latter placed on the porion and the upper across the top of 

 the cranium, directly upon the bregma. 



5. Least frontal breadth; the distance between the two fronto- 

 temporalia. SC. 



6. Greatest frontal breadth; the largest measure that can be obtained 

 by the slide compass, both points of the instrument being placed on the 

 lateral edges of the frontal bone; the distance between the two coronalia. 

 SC. 



7. Bimastoid breadth; the distance between the most lateral portions 

 of the outer surfaces of the two mastoid processes, measured perpendicu- 

 larly to the median plane (cf. modification of this below). Cr. 



8. Bizygomatic breadth; the greatest breadth obtained by measuring 

 across the zygomatic arches, perpendicularly to the median plane. The 

 points where the two feet of the compass rest when this measurement is 

 obtained are the zygia, movable points like the opisthocranium. 

 Cr or RC. 



9. N asion-basion line; the distance between the two points named. Cr. 



10. Prosthion-basion line; the distance between the two points named. 

 CrorSC. 



11. Nasion-gnalhion line; the distance between the two points named. 

 The mandible must be put in place, the teeth in contact, and the condyles 

 resting in the mandibular (glenoid) fossae of the skull. SC or RC. 



12. N asion-prosthion line; the distance between the two points named. 

 SC or RC. 



13. Nasal length; the upper limit for this is the nasion; the lower is 

 theoretically the nasospinale. Since this latter point is usually within 

 the substance of the bony process forming the nasal spine, the lowest point 

 of the lower margin of the nasal aperture, a little on one side of the median 

 line, is used instead (cf. under Landmarks; subspinale, above). SC. 



14. Nasal breadth; the greatest breadth found within the lateral mar- 

 gins of the nasal aperture, measured horizontally; i.e., perpendicularly to 

 the median plane. SC. 



