GENERAL CONSIDERATIONS. 



1033 



elevation of the forehead ; but it does not appear that there is a corresponding 

 diminution in the capacity of the cranial cavity, the retreating form of the fore- 

 Fig. 284. 



Profile and basal views of the Prognathous Skull of a Negro. 



head being partly due to the general elongation of the skull in the antero-poste- 

 rior direction. Nor is it true, as stated by some, that the position of the fora- 

 men magnum in the Negro is decidedly behind that which it holds in the 

 European, in this respect approaching that of the Apes ( 2) : since, if due 

 allowance be made for the projection of the upper jaw, this aperture is found to 

 have the same position in the prognathous skull as in the oval one, namely, 

 exactly behind the transverse line bisecting the antero-posterior diameter of the 

 base of the cranium. The prognathous skull is further remarkable for the 

 large development of the parts connected with the organs of sense, especially 

 those of smell and hearing. The aperture of the nostrils is very wide; and the 

 internal space allowed for the expansion of the Schneiderian membrane, and for 

 the distribution of the olfactory nerve, is much larger than in most European 

 heads. The posterior openings of the nasal cavity are not less remarkable for 

 their width, than the anterior. The external auditory meatus is also peculiarly 

 wide and spacious; and the orbital cavities have been thought to be of more 

 than ordinary capacity but this last is by no means a constant character. 



1040. A second type of cranial conformation, very different from the pre- 

 ceding, belongs principally to the Nomadic races, who wander with their herds 

 and flocks over vast plains ; and to the tribes who creep along the shores of the 

 Icy Sea, and live partly by fishing, and in part on the flesh of their reindeer. 

 This form, designated by Dr. Prichard as the pyramidal (Fig. 285), is typically 

 exhibited by various nations of Northern and Central Asia; and is seen, in an 

 exaggerated degree, in the Esquimaux. Its most striking character is the lateral 

 or outward projection of the zygoma, which is due to the form of the malar bones. 

 These do not project forwards and downwards under the eyes, as in the progna- 

 thous skull; but take a direction laterally or outwards, forming, with the zygo- 

 matic process of the temporal bone, a large rounded sweep or segment of a 

 circle. From this, in connection with the narrowness of the forehead, it results, 

 that lines drawn from the zygomatic arches, touching the temples on either 

 side, instead of being parallel (as in Europeans) meet over the forehead, so as to 

 form with the basis a triangular figure. The upper part of the face being re- 

 markably flat, the nose also being flat, and the nasal bones, as well as the space 

 between the eyebrows, being nearly on the same plane with the cheek-bones, 



