4^ Proceedings of the Royal Physical Society. 



a " chin " does not exist except in man. It is better, there- 

 fore, to take the length of the face as being the distance 

 between the nasion and the alveolar point (Fig. 4, g). 



Breadth of Face. — It is believed that the most generally 

 useful measurement of the breadth of the face is one 

 between points on the sutures between the malar and 

 maxillary bones. In many animals there is a well-defined 

 ridge running downwards and forwards from the zygoma. 

 This ridge is largely developed in the Equidse. Even when 

 the ridge does not attain any very marked prominence, its 

 representative is usually not very difficult to find. Mostly 

 the ridge forms the most lateral part of the face ; and so it 

 seems natural to use it in gauging the facial breadth. In 

 order that the measurement be taken from a fixed point, we 

 may determine upon the spot where this ridge crosses the 

 malo-maxillary suture (Fig. 3, c, and Fig. 4, c). 



Length of Palate. — The length of the palate may be readily 

 determined by measuring along the middle line from the 

 centre of its posterior border to just behind the incisor teeth. 

 In some skulls there is a spine of variable dimensions pro- 

 jecting backwards from the middle of the curved posterior 

 palatal border. In such cases the process should be 

 excluded from the measurement. 



Breadth of Palate. — In those skulls where the posterior 

 border of the palate lies anterior to the last tooth, the 

 palatine breadth can be taken along a transverse line on 

 a level with the most anterior part of the curve of the 

 posterior palatal border. When the posterior border falls 

 behind the dental series, the breadth should be taken 

 between the last teeth (Fig. 3, b). In either case, because 

 of the relative difference in size of the teeth of different 

 animals, the palatal breadth should not include them. 



Cranio-facial Length. — The length of the entire skull may 

 be expressed in a cranio-facial diameter measured from the 

 opisthion to the alveolar point (Fig. 4, h). Some anatomists 

 have measured the length of the entire skull from the 

 alveolar point to the crest formed by the occipital bone; 

 but, as already pointed out, this crest is too variable to be 

 of use in making measurements. 



