OSTEOMETRY; THE MEASUREMENT OF THE BONES 



47 



nasion (n) 

 nasospinale (ns) 



obelion (ob) 



ophryon (on) 



opisthion (o) 

 opisthocranion (op) 



(ol) 



orbitale (or) f 

 pogonion (pg) 

 porion (po) f 



prosphenion (ps) 

 prosthion (pr) 



pteryon (pt) f 



The upper end of the internasal suture, where 

 it meets the frontal bone; the point where the two 

 nasal bones and the frontal come together. 

 This is practically the acanlhion, the "nasal spine" 

 of the older authors, but avoids the frequent errors 

 caused by the varying degree of development found 

 in this process. This point is defined as a point 

 (usually within the bone substance), where a line 

 tangent to the two lateral curves of the lower 

 margin of the piriform aperture crosses the median 

 line. In practice it is usual to take the lowest point 

 of this margin upon one side of the median line. 

 The point in the sagittal, or interparietial, suture 

 where it is intersected by a line drawn to connect 

 the two small interparietal foramina. In the 

 frequent cases in which there is but one of these, 

 this point may be readily determined by it, and 

 where both are absent, the point lies approximately 

 at the place where the suturing is the simplest. 

 . The point in the median line of the frontal bone 

 where it is crossed by a line drawn to connect the 

 two fronlolemporalia. 



The median point of the posterior margin of the 

 occipital foramen. 



This point is anatomically an indefinite one, and 

 is simply the posterior end of the maximum length 

 line of the skull, drawn from the glabella; the point 

 where the posterior leg of the compass rests when 

 spanning the greatest length. It may coincide 

 with the inion, but is usually above this point. It 

 is a synonym for exlremum occiput and occipitale. 

 A point in the bony palate where the line drawn 

 tangent to the curves in the alveolar margin back 

 of the two medial incisor teeth crosses the median 

 line (Fig. 25). 



The lowest point in the margin of the orbit; one of 

 the points used in denning the Frankfort Horizontal. 

 The most projecting median point of the chin, on 

 the anterior surface (mental process). 

 The uppermost point in the margin of the auditory 

 meatus; the points which, with the orbit alia, define 

 the Frankfort Horizontal. 



The median point in the spheno-ethmoidal suture 

 upon the inner surface of the skull (Fig. 11). 

 The lowest point of the intermaxillary suture, upon 

 the alveolar margin, between the two medial in- 

 cisors. 



This is a region, rather than a point, and desig- 

 nates the upper end of the greater wing of the 

 sphenoid, with the bordering bones, frontal, pari- 

 etal, and temporal. Here the relation of these 

 bones, and consequently of the sutures, is markedly 

 variable, and is the subject of special anthropological 

 interest. 



