104 



THE SKELETON. 



presents three rows of foramina for the transmission of its nervous filaments, 

 and in front a slit-like opening for the nasal branch of the ophthalmic division 



Groove for superior longitudinal sinus. 



Grooves for anterior meningeal artery. 



Foramen caecum. 



Crista galli. 



Slit for nasal nerve. 



Groove for nasal nerve. 



Anterior ethmoidal foramen. 



Orifices for olfactory nerves. 



Posterior ethmoidal foramen. 



Ethmoidal spine. 



Olfactory grooves. 



Optic foramen. 



Optic groove. 



Olivary process. 



Anterior clinoid process. 



Middle clinoid process. 



Posterior clinoid process. 



Groove for 6th nerve. 



Foramen lacerum medium. 



Orifice of carotid canal. 



Depression for Gasserian ganglion. 



Meatus auditorius internus. 



Slit for dura mater. 



Superior petrosal groove. 



Forainen lacerum posterius. 



Anterior condyloid foramen. 



Aquseductus vestibuli. 



Posterior condyloid foramen. 



Mastoid foramen 

 Posterior meningeal grooves. 



Fis. 71. Base of the skull. Inner or cerebral surface. 



of the fifth nerve. On the outer side of each olfactory groove are the internal 

 openings of the anterior and posterior ethmoidal foramina ; the former, situated 

 about the middle of the outer margin of the olfactory groove, transmits the 

 anterior ethmoidal vessels and the nasal nerve, which latter runs in a depression 



