OSTEOMETRY; THE MEASUREMENT OF THE BONES 



45 



hormion (h) 

 infradentale (id) 



inion (i) 



klitiim (k) 



lambda (1) 

 lacrimale Qa) f 



diately behind which there is at least the suggestion 

 of a tubercle. This is the point taken as the gonion. 

 The median point in the suture between vomer 

 and sphenoid; the median point where the former 

 overlaps the latter. Seen in norma basilaris. 

 The highest point in the anterior alveolar mar- 

 gin of the mandible in the median line, between 

 the two medial lower incisors. It corresponds 

 to the prosthion of the upper jaw. 

 This point, although one of the first employed 

 and named, was rather loosely designated as the 

 highest point in the occipital protuberance, or 

 even as simply the occipital protuberance it- 

 self. It was furthermore considered to be the 

 most posterior point in the outer surface of the 

 skull, so that the "glabella-inion line," drawn 

 between the two points named, was considered to 

 measure the maximum length. In some skulls 

 this may be the case, but more often such is not 

 the case, hence the establishment of the opistho- 

 cranion, as the terminus of the maximum length 

 line, which may or may not coincide with the inion. 

 In the majority of skulls it may be denned in its 

 original intention as the center of the occipital 

 protuberance, although it should never be placed at 

 or near the end of an elongated, downward-project- 

 ing process, which sometimes occurs. When the 

 occipital protuberance is weak or ill-defined, the 

 inion may be ascertained as the point where the 

 superior curved (nuchal) lines cross the median 

 plane. 



An internal inion, the endinlon, is located at the 

 crossing of the crucial ridges which divide the 

 cerebral and cerebellar fossae. Its position may 

 be determined by inserting the thumb into the 

 occpital foramen, and when this is done the fore- 

 finger can readily determine the external point 

 directly opposite it. Some observers use this ex- 

 ternal point, opposite the endinion, as the true 

 inion, and determine it by this means, marking 

 its position upon the outer surface with a pencil. 

 In many cases these two inia will be found to co- 

 incide, but as this is not always the case, it is recom- 

 mended for each investigator to state definitely 

 which point he uses. 



A median internal point, best located in a median 

 sagittal section, as hi Fig. 26. It is the median 

 point in the posterior margin of the sella turcica, 

 which lodges the hypophysis in life, and is thus 

 placed opposite the tylion. 



The meeting place of the sagittal and lambdoidal 

 sutures, of the two parietal bones with the occipital. 

 The point of intersection of the posterior lacrimal 

 crest with the fronto-lacrimal suture (Fig. 24). 



