REMOVAL OF THE BRAIN 



207 



In order to expose it, the cerebral veins must be divided as 

 they open into the superior sagittal sinus, and the hemisphere 

 gently pulled laterally. Anteriorly, the falx cerebri is narrow, 

 and attached to the crista galli of the ethmoid bone. It 

 increases in breadth as it passes backwards, and posteriorly 

 it is attached in the median plane to the upper surface of 

 the tentorium cerebelli. The anterior part of the falx is 

 frequently cribriform, and is sometimes perforated by apertures 

 to such an extent that it almost resembles lace-work. Along 



Superior sagittal sinus 



Falx cerebri 



Cerebellar fossa 



Transverse sinus 

 Cerebellar fossa 



FIG. 87. Frontal section through the Cranial Cavity in a plane which passes 

 through the posterior part of the foramen magnum. The posterior 

 part of the cranial cavity, from which the brain has been removed, is 

 depicted. 



each border its two layers separate to enclose a blood-sinus. 

 Along its upper convex margin runs the superior sagittal 

 sinus along its concave free border courses the much smaller 

 inferior sagittal sinus ; whilst along its attachment to the 

 tentorium is enclosed the straight sinus. Its inferior concave 

 margin overhangs the corpus callosum, with which, however, 

 it is not in contact, except to a very slight extent, posteriorly. 



Removal of the Brain. The dissectors should now proceed to remove 

 the brain. Having divided the attachment of the falx cerebri to the 

 crista galli, pull it posteriorly. Next, removing the block upon which 

 the head rests, and supporting the occiput and posterior lobes of the brain 

 with the left hand, let the head drop well downwards. In all probability, 

 the frontal lobes will fall away by their own weight from the anterior fossa 



