356 EEVIEWS. 



this line invariably as the vertical line of the skull, and it will be found 

 in the vast majority of cases really to be so (VV. Fig. 1. PI. VIII.). 

 Now, if a line be drawn at right angles with this, also through the 

 centre of the auditory foramen (HH. Fig. 1), it will be found to run 

 in the same plane with the zygoma, and to cut the nostrils at a vari- 

 able distance above their floor ; — the distance varying according to 

 the downward development of the superior maxillary bones, and thus 

 affording, in some cases, a useful character. This we regard as the 

 horizontal or base line of the cranium. 



2. With respect to certain points in the cranium from Avhich 

 some of the measurements are to be taken. The more important of 

 these appear to us to be — 



1. The fronto-nasal suture, from which the measure of the longi- 

 tudinal arc commences, and to which the fronto-nasal radius is 

 measured. 



2. The posterior border of the foramen magnum. 



3. Tlie most important of all — the centre of the external auditory 

 foramen. If a wire be passed directly through this point, it wiU 

 enter the cavity of the skull through the internal auditory opening, 

 and pass out at the other side, of course in the same direction, tra- 

 versing the pons varolii, and thus nearly corresponding with the 

 point at which the cruxa-cerebri begin to expand. Lines radiating 

 from this point to the surface of the brain will consequently give 

 pretty nearly the depth of that organ in the various directions. In 

 the same way, if similar radial lines can be drawn to points on the 

 exterior of the skull, these wiU aff"ord a rough approximation to the 

 depth of the brain in the given directions. At any rate, they wdU 

 afford data for the comparison of one skull with another. From the 

 same point also are measured the transverse arcs, wliich coiTCspond 

 in direction with the radii of the same denomination, and afford a 

 comparative idea of the greater or less convexity of the craniimi in 

 the different regions. 



4. The occipital spine. 



5. The anterior border of the alveolus of the upper jaw. To this 

 point is measured the maxillary radius, and the diftereuce in length 

 between this and the fronto-nasal radius wiU be found, perhaps, a 

 better criterion of the degree of projection of the jaws than is 

 afforded by any of the uncertain means hitherto devised for ascer- 

 taining the so-termed facial angle. 



G. The most projecting points in the zygomatic arches. 

 7. The external angular processes of the frontal bone. 

 It will be necessary to add but a few words further explanatory 

 of the measurements in the table ; which will, however, better be 

 imderstood by reference to the figures in the accompanying plate 

 than by any detailed description. In — 



Fig. 1. (Plate VIII.) V, V, is the vertical line, and also the direc- 

 tion in which the vertical radius and transverse arc 

 are measured. 



