CEREBRAL LOCALIZATION 215 



It is well known that even if a cerebral tumour 

 cannot be localized, palliative trephining should be 

 performed to relieve headache and save the sight. 

 If this is undertaken early, the optic neuritis passes 

 off. As the tentorium transmits pressure badly, 

 the trephining should be in the temporal region for 

 supratentorial tumours, and in the occipital region 

 for cerebellar tumours. 



Another valuable observation which we owe to 

 Gushing is that raised intracranial pressure, par- 

 ticularly by cerebral tumour, induces a considerable 

 limitation of the field of vision for blue ; indeed, 

 there may be actual blue-blindness. 



THE CEREBELLUM. 



We have been in urgent need of some improvement 

 in our means of localizing tumours and abscesses 

 in the cerebellum. During the past ten years, at the 

 Bristol Royal Infirmary there have been eight cases 

 of temporo-sphenoidal abscess, all of which have 

 been successfully diagnosed, and ten cases of cere- 

 bellar abscess, of which only three were correctly 

 located ; in three of these ten cases the cerebrum 

 was explored in vain, and in two the lateral sinus 

 was thought to be the cause of the symptoms. It 

 remains to be seen how far the fresh light recently 

 thrown on the subject and herein set forth will 

 help us to obtain materially better results. 



Sir Victor Horsley and R. H. Clarke have recently 

 revised our knowledge of the functions and relation- 

 ships of the cerebellum by an ingenious method. 

 Reconstructions of a monkey's head have been made 



