viii THE HUMAN EACES 331 



types of cranial formation we have a large number of intermediate 

 shapes known as mesocephalic (medium-headed people). 



In each of these three groups we find some who are pro- 

 gnathous (oblique jawed), in which the jaws project as does the 

 snout of the lower mammals and the incisors slope outwards, and 

 others who are orthognathous (straight jaws or teeth), in which 

 the jaws are less developed and prominent, so that the incisors 

 are vertical (Fig. 140). 



We have also two extreme types in the shape of the whole 

 face, just as in that of the skull : the long narrow face 

 (dolichoprosopia or leptoprosopia) and the short broad face 

 (brachyprosopia or prosopia) (Kollmann and Eanke, Fig. 131). 



When forming an estimate of the different normal morpho- 



Fio. 131. 1, Narrow or dolichoprosopic face ; 2, broad or braehyprosopie face. (Kollmann.) 



logical characteristics, and more especially of those of the skull, 

 we must of course eliminate the effects produced by pathological 

 modifications, such as microcephaly, hydrocephaly, scafocephaly, 

 acrocephaly, plagiocephaly, clinocephaly, due for the most part 

 to embryonic or post-embryonic changes occurring during the 

 ossification of the different bones of the skull ; we must further 

 eliminate the results of artificial deformation of the skull, such 

 as is customary amongst various races of America (Indians), 

 Australia (New Hebrides and New Britain), and Europe 

 (Normandy and Brittany), which are brought about by means 

 of compression with bandages in infancy when the skull is in 

 process of development and still soft. 



Amongst other bodily, characteristics is the formation of the 

 retrosacral fossa, which the investigations made recently by 

 L. Bolk amongst the Dutch and Melanesians, and those of 



