THE CEREBRUM 



1 1 



of the corpus callosum extends forwards from the splenium 

 to the genu, where it bends sharply downwards and backwards 

 to end in a pointed extremity, which is termed the rostrum. 



Cases of maldevelopment or congenital absence of the 

 corpus callosum have been recorded, but, although some 



Septum pellucidum 

 Corpus calionmi x \ Fornix 



[nterventricular foramen" 

 Lamina terminal!* 



Oculomotor nerve 

 Pon 



. Middle commissure 



_ - Pineal body 



Corpora quadrigemina 



_ Cerebral aqueduct 

 (of Sylvius). 



Fourth 

 ** ' ventricle 



_ _ Central canal of 

 spinal medulla 



FIG. 5. Median Sagittal Section through the Brain-Stem, showing the 

 third and fourth ventricles and their connexions: 



were associated with mental dulness, others appear to have 

 produced no symptoms during life and were only discovered 

 accidentally in the post-mortem or dissecting room. Four 

 cases of tumour involving the corpus callosum, three of which 

 were primary, have been described by Bristowe, who believes 

 that it may be possible to recognise the condition during the 



