8 



SUPERFICIAL ANATOMY OF THE HEAD AND NECK. 



backwards for 35 mm., and from the end of this a vertical line for 12 mm. upwards ; 

 the upper end of the latter line marks the spot where the anterior branches are 

 given off from the Sylvian fissure, and may be termed the Sylvian point. A line 

 drawn from the fronto-malar junction through the Sylvian point to the lower part 

 of the parietal eminence will about lie over the posterior limb of the Sylvian fissure, 

 and may be called the Sylvian line. The anterior ascending and horizontal branches 

 of the fissure may be marked by lines 2 cm. long starting from the Sylvian point, 



SUP ROLAND.C POWT 



UMBDA 



INIO'N 



Fig. 5. SIDE VIEW OF SKULL ON WHICH THE CHIEF POINTS AND LINES USED IN CKANIO-CEREBRAL 

 TOPOGRAPHY HAVE BEEN MARKED. 3. (From a photograph by G. W. B. Waters.) (G. D. T. ) 



The contour of the cerebral hemisphere, with the Rolandic and Sylvian fissures, are marked by 

 continuous red lines, and the outline of the insula and of the lateral ventricle by broken red lines. 



the one directed upwards and forwards at right angles with the Sylvian line, and the 

 other horizontally forwards. 



On the Sylvian line, 25 mm. behind the Sylvian point, is the lower Rolandic 

 point, the spot where the fissure of Rolando, if prolonged, would meet the Sylvian 

 line. The lower Rolandic point is about 5'5 cm. (varying from 4 to 7) above the 

 upper border of the zygomatic arch, on or slightly in front of a vertical line passing 

 through the preauricular point. The Rolandic line may now be drawn between the 



