THE OLFACTORY NERVES 



49 



Fractures of the anterior cranial fossa may injure either the 

 olfactory bulbs or nerves and give rise to anosmia. The 

 olfactory nerves are restricted to the uppermost parts of the 

 nasal fossae, and these areas are rarely reached by local 



Foramen 



caecum Crista galli 



x Lamina cnbrosa of ethmoid 



Position of optic chiasma 

 x Optic foramen 

 ^ Hypophyseal (pituitary) fossa 

 ., Superior orbital (sphenoidal) fissure 

 Foramen rotundum 



Foramen ovale 

 Foramen spinosum 



, Internal acoustic meatus 

 ^.-Jugular foramen 



H Groove for transverse (lateral) 



sinus 

 Mastoid foramen 



m 



FIG. 27. Floor of Skull. 



anaesthetics. Consequently, although cauterisation of the 

 mucous membrane of the inferior meatus of the nose may be 

 carried out quite painlessly under local anaesthesia, the patient 

 is acutely conscious of the disagreeable odour of the charred 

 tissue. 



