Chap. III.] 



THE CRANIAL CONTENTS. 



29 



The relations of the brain to the skull. 



The lower level of the brain in front corresponds to a 

 line drawn across the forehead just above the eye- 

 brows. At the side of the head it corresponds 

 approximately to a line drawn from a point half an 

 inch above the external angular process of the frontal 



Fig. 7. Diagram to show the Eelations of the Main Fissures to the 

 Surface of the Skull. 



to the upper part of the external auditory meatus. 

 A line drawn from this latter spot to the occipital pro- 

 tuberance corresponds to the lower level of the posterior 

 lobe, while below that line will lie the cerebellum 

 (Fig. 7). The commencement of the Sylvian fissure 

 corresponds to the pterion. Its ascending limb is 

 parallel to, and immediately behind, the coronal suture. 

 Its posterior, or horizontal limb, runs backwards 

 across the upper margin of the squamous suture. 

 The external parieto-occipital fissure is a little in front 

 of the lambda. The fissure of Rolando is some way 

 behind the coronal suture, and is not quite parallel to 



