568 DESCRIPTION OF FIGURES OF SKULLS. 



rohres tind iiher die Stelhmg des Schddels auf die Wirlelsdide beim Neger 

 mid beim Europder. The same indication is given in a less precise 

 way by placing a skull with the grinding surface of its upper-jaw 

 teeth upon a flat surface and then observing whether it is the 

 occipital condyles or the conceptaeula cerebelli which furnish a sup- 

 port to the back part of the skull when it is brought down on to 

 that surface. This method however of estimating the extent of 

 cranial curvature is not rarely likely to mislead us. For in skulls 

 of adults, and especially of male adults, the occipital condyles are 

 often found to have increased considerably in a downward direction ; 

 and such skulls may then come, when placed as above directed, to 

 rest upon them, owing, not to any deficiency in the cranial curvature 

 or length of the brain, but simply to this outgrowing of the condyles 

 which is developed in aid of the maintenance of the balance of the 

 head in the horizontal position, as pointed out by Professor Cleland, 

 Phil. Trans. 1870, p. 161. 



Of the several norma, the norma lateralis or profile view of a skull 

 is the most important, giviug as it does, firstly, the most character- 

 istic view of the upper and lower jaw, secondly, the relation of 

 height to length, and, thirdly, the picturesque peculiarities of the 

 antero-posterior curve of the cranial vault ^. The upper contour 

 line, in fact, of a brachy-cephalic skull viewed in profile, dipping 

 away, as it does, more or less abruptly downwards in a plane but 

 a little posterior to that of the parietal tubera, distinguishes such a 

 skull from dolicho-cephalic forms as sharply as the proportion seen, 

 in its vertical norma, to be borne by its transverse to its longitu- 

 dinal diameter. The possession in fact of such a contour line may 

 justify us in considering a skull to belong to the brachy-cephalic 

 division and in speaking of it as ' brachy-cephalic by contour,' even 

 though its extreme breadth may bear a less favourable ratio than 

 that of 80 to 100 of its extreme leno'th. 



It may be well to state here that the ' precipitous sinking' away 

 of this contour line is very frequently due to an abrupt curvature of 

 the parietal bones exclusively; and that, contrary to what has some- 

 times been laid down, the superior occipital squama may be ' full 

 and globular ' in a brachy-cephalic skull, standing out in a plane 

 posterior to that occupied by the posterior portion of the parietals, 



' Clclaucl, Phil. Traus. 1870, p. 145, and Retzius, Ethnolog. Schriften, pp. 118-121. 

 cit. in loco. 



